Dutch passport for my son

Question: My father is a Dutch passport holder as are my sister and brother and my sister's two children. Apparently I am too old to get a Dutch passport. I would like to know if my son can get a Dutch passport as his Opa has one.
Comment: This is a complicated issue; take a look at Wikipedia's Dutch Nationality article: https://en.wikipedia.org/wiki/Dutch_nationality_law#By_descent_or_automatic_acquisition_of_Dutch_nationality To assess your son's eligibility, one would need to know where and when you were born, where and when your son was born, where you and he have lived since your births, whether or not you and he have taken citizenship or secured a passport from another country, and if so, when. That's off the top of my head, I may well have missed a few data points.
Answer: David's comment is essentially correct.  Your son cannot get a Dutch passport by virtue of his grandfather's nationality.  But he might be a Dutch citizen if all of the following are true:

You were Dutch when you were born.
You were Dutch when he was born.
You passed Dutch nationality to him at his birth (that is, either he was born after 1985 or, if he was born before 1985, he was born out of wedlock and without any legal father).
You did not lose Dutch nationality before he reached his 18th birthday.
He has not yet reached his 28th birthday.

I've done this off the top of my head, so I might have a detail or two wrong, and there are some very unlikely exceptions that, if he reaches the last step, might extend the deadline past his 28th birthday.
Comment: Point 1 is really a prerequisite to point 2; it's not strictly necessary by itself.

Dutch passport for my son


Pathfinder Kingdom Builder: How big, area wise, is a hex?

Question: I know that every kingdom is constructed out of hexes and it's the basis for how large a kingdom is.  This goes into what improvements it can have, how many, where the settlements are, ect.  But one thing I'm having a hard time finding is how large, physically, those hexes are.  Even if I can get a ballpark number, I need something to try and outline the scale of the land mass that I'm trying to create and how many hexes to break it up into.  A good example of known landscapes and land masses with hex grids on already would also be helpful.
Answer: d20PFSRD on Kingdom Building:

Like the exploration system, the kingdom-building rules measure terrain in hexes. Each hex is 12 miles from corner to corner, representing an area of just less than 95 square miles. The hex measurement is an abstraction; the hexes are easy to quantify and allow the GM to categorize a large area as one terrain type without having to worry about precise borders of forests and other terrain features.
Comment: @GMJoe Mathematicians/engineers apparently have the opposite convention as RPGs. You sanity check the meaning though, because [otherwise](http://www.had2know.com/academics/hexagon-measurement-calculator.html) you get hexes of ~375 sq. miles instead of ~95.
Comment: "Corner to corner" has apparently been misunderstood by some people ([including 3PP designers](http://paizo.com/threads/rzs2nqas?Travel-distance-movement-and-hex-sizes-in)) to mean the length of one edge. So for the record: that's 12 miles across the middle at the widest point.
Comment: Of course, the one paragraph that I'm looking for is the one I seem to have read over without realizing it.  Thanks!
Answer: In every other game I've ever played, hexes are measured by their edge to edge distance, because that is the way you move from one to another. For whatever reason, PF says their 12 mile hexes are measured corner to corner, which gives an edge to edge distance of about 10.4 miles.
The area of said hex is a bit over 93.5 square miles, which is close to 100 square miles, a nice round number. I suspect that is the reason why. The area of a hex 12 miles across is a bit under 125 square miles.
In my works, I have used the edge to edge distance (like everyone else in the entire world does) of 12 miles. This is exactly 4 hours to walk across for someone whose speed is 30, or allows 2 hexes of travel per day along roads without having to force-march. (For people whose speed is 20, this is 6 hours to cross a hex, and for those with a speed of 40 it's 3 hours to cross; very easy math for the bulk of situations.) It's also a lot closer to 125 square miles than a 10.4 mile hex is to 100, meaning I have vastly smaller rounding errors.
Comment: This seems to consist of more side discussion than focused answer. You might want to improve it as an answer by reducing the focus on things that aren't answering how big PF Kingdom Builder hexes are and focusing more on the topic. (If this seems an odd recommendation, consider that this site is not a discussion forum, and this is not a threaded discussion.)
Comment: Sorry, meant to add: an easy way to find the area of the hex is to square the edge to edge distance, then multiply by 7/8. (The more precise number to multiply by is sqrt(3/4).)

IIRC, you may alternately square the corner to corner distance and multiply by 3/4 as an approximation.
Comment: Hi, and welcome to RPG Stack Exchange! Check out our [tour] to see how we work here. You should edit that into your post via the edit button in the bottom left -- comments are transient and get cleaned away eventually. We also have a full edit history of posts, so just put it wherever you would do so (avoid using an "edit:" section like one does on a forum).


Will my approvals be deleted if I click on "End this workflow" in SharePoint 2013?

Question: My workflow has completed and is approved however the first approver keeps getting notifications that his task is overdue. I can see he completed his task.  I want to stop the workflow but not delete the completed workflow history. When I click on "End this workflow" I get a message that says, "This will delete any previously created tasks".  There are no pending tasks so I'm afraid this will delete the completed tasks.
Answer: that would delete the tasks, but not the workflow history
the workflow tasks is a separate list that contains the required approvals
but any workflow history log linked to the tasks will be removed
the best practice to avoid this problem is to add "log" actions during the workflow execution for the next workflows


How can I create a car mod for GTA: Vice City?

Question: I am a player of GTA games. I want to create my own car for GTA: Vice City. How do I create a mod that adds a new car to the game?
Comment: N.B. that *modding questions are on-topic here*.
Comment: I Know about **sanny buider** -  a tool for creating `dff` and `txd` files. but it not works for me. so i am asking this question.
Answer: To make a totally new car, you'll first have to model it in 3D in a modelling program. Blender is a reasonable freely-available modelling tool.
Once you've got the model, you need to export it into the .dff file format used by Vice City. This plugin can export from Blender to .dff; you can find plenty of other .dff exporters for other modelling tools as well if you search around.
The G-IMG tool can be used to edit GTA's archive files and install your custom .dff (and associated .txd). The .dff and .txd files exported for the car are the basics needed to get the car in game; the rest allows you to customize and tweak the car.
The CFG Studio tool can be used to install any custom handling.cfg (which is just a text file) parameters for your car. This car editor can also edit handling and color files for your car.
This guide covers the basic steps in more detail.
Comment: thank you and +1 for understand my question and for answer.


How do I go about choosing image height on a background-cover div?

Question: I have a slider on my page with the property background cover applied so it fits the whole thing. The slider also has a 50vh fixed height. The background always ends up cutting things from the image that I don't want. How should I go about choosing the right width x height knowing that the website will be seen in very different devices ?
Comment: This is far too broad and unclear to be answerable in any way. How could we possibly know what the right width or height of an element in your design is when we have no idea what it's supposed to look like?
Comment: Figure out the max height it will ever display on the largest screen (from 800-1200 px) and make your image that height x 4 times as wide. (so h1000px x w4000px). Forget about controlling exact content or borders on the image. It needs to be a large general field with best stuff in center top. Expect it to get cropped a lot, always centered with fixed top. Phones will only see a narrow middle top section. Big screens will see the whole thing.
Comment: [Reading the docs](https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Background_and_Borders/Scaling_background_images) should help. But given there's no code to help debug and it's not clear what you want, we can't really help you. Questions like this would probably fit better on StackOverflow anyway
Comment: @Webster Please avoid answering questions in the comments. This is an answer that I'd upvote. Thanks.
Answer: First of all, if your website is going to be seen in lot of different devices, you should use relative width on the elements. You're setting the heighton your slider, so it'll obey that rule, making some of the banner to be cropped off to prevent image distortion.

Use the viewport meta tag to set the width of the body element to be the same as your device width. <meta name="viewport" content="width=device-width, inicial-scale=1"> this will help you with some other resposive problems.
Use the width property to size your elements: stick with relative values, such as 100% , 75% etc.
Create media queries to prevent your banner on looking too large on big screens.

You can read more about responsive web design here
Answer: You have a slider with height 50vh (50% of viewport height) thus whenever the screen size changes the slider size will change, thus it will be difficult to adjust a raster(png, jpg) image that will keep the same aspect ratio everywhere.
The options are either you make the height of the slider fixed and then choose an image according to that height or use some vector based images in slider.


Combustion Chamber Back Pressure due to gas injection

Question: I am trying to calculate prior to testing the expected back pressure resulting from injecting gaseous oxygen through an injector orifice (choked) into a rocket combustion chamber before ignition. I have tried using the Borda-Carnot equation with the assumption that the chamber mean flow is sufficiently low and that the pressure differential between the chamber and atmosphere is sufficient to drive the same mass flow through the nozzle that was injected into the chamber. Calculating the delta P under these assumptions yields an unreasonably small delta P across the nozzle. Is there a hand-calc method available that would provide some insight to this? I know that there are highly localized dynamics in the gas flow that are likely going to cause significant deviation from the analytical values, but I am mostly looking for a first-order estimate.
Answer: I believe that the Borda-Carnot equation is only valid for incompressible flows, while you mention that the injector orifice is choked. While the flow becomes incompressible pretty quickly after the orifice, at this precise point, it is not.
In this case, I think you should use 1D isentropic nozzle theory (wikipedia offers a good start on the topic).
If the injector orifice is choked and there is no shock in the injector channel or downstream of it, then the pressure ratio should be
$$
P_{res}/P_{a} = \left(\frac{\gamma+1}{2}\right)^{\frac{\gamma}{\gamma-1}}
$$
with $P_{res}$ the tank pressure, $P_a$ the ambient pressure, $\gamma = \frac{c_p}{c_v}$ the ratio of heat capacities.
That's assuming you are injecting gas into gas. If the fuel in the tank is liquid, then the situation is different because of evaporation.


How can I characterize a histogram/distribution with a single value?

Question: I have histograms/distributions like the following that I would like to characterize/summarize by one or maybe two number(s). A mean +/- std would be one such example, but is there something better that can say something about the shape of the distribution? Most of the times the most frequent values are near the two ends, so the distributions are not normal. Is there a statistic for being the opposite of normal distribution?

Comment: Besides mean and standard deviation, there are summary measures like skewness and kurtosis to quantify the shape of a distribution. But that makes four numbers...
Comment: Thanks, but for the distributions that I have, I'm not sure if skewness and kurtosis will make much sense, since they are not normal or 'normal-like' distributions.
Comment: Say they are bimodal perhaps and then give the modes?
Comment: Thanks, that's a good suggestion, but they are not always bimodal.
Answer: The simple answer is: You can't.
Slightly more complex answer: The reason you can summarize a Normal distribution with two numbers is that, once you have the mean and the SD of a Normal distribution, a lot of the rest is determined. While there can be variations in any particular sample, the skewness of a Normal is 0, the excess kurtosis is 0, it's symmetric and you can estimate the number that will be in any bin of a histogram.
If you are willing to assume another distribution, then you may be able to summarize the data with one, two, three or four values, depending on the particular distribution. For instance, a Poisson distribution can be summarized with one value.
However, if you are not willing to make that assumption, then any summary will lose a lot of information. You could use range or interquartile range for spread, and median or another trimmed mean for location, but this will be much less informative than mean and sd for a Normal.
Comment: Thank you for your answer. Someone mentioned about a U-quadratic distribution. Is there a way to summarize a distribution like that? Or test whether a distribution follows that pattern?
Answer: Could it be that your data follows the family of U-shaped distributions?
https://en.wikipedia.org/wiki/U-quadratic_distribution
Comment: Thanks a lot! I think this might help. I didn't know how to name a distribution like this. Are you familiar of any statistical tests that allow you to find whether a distribution is U-quadratic? Any Python/R/Matlab implementations that you know of might also be helpful.
Comment: If you are familiar with R, you could use the "fitDistr" function of my 'propagate' package which fits 31 (!) different distributions and selects the one with lowest BIC. There is a U-shaped one inside: Arcsine dist.
Comment: Awesome! That is very helpful. Thank you! Yes, I think arcsine would fit the data best.
Answer: What if I convert the distribution to a Cumulative distribution function like this? Can you use the beta parameters or something like that?


does validating MAC of individual packets validates the integrity of whole file?

Question: When transferring a large file over network, its likely that the file is broken into packets and then transferred. The underlying network protocol, lets consider the case of TLS/SSL, it generates MACs for the individual packets, the receiving party compares the MAC and is guaranteed that the MAC of individual pieces are correct. Does this ensure that the complete file on transfer is not corrupt, assuming no packet/chunk is lost on wire?
Answer: The MAC in SSL/TLS is computed over the combination of the record payload and a sequence number, thus ensuring that records are all received, with no missing, out-of-order or duplicated record. The connection is also terminated with an explicit close_notify alert, which is itself part of the protected records, thus cannot be faked by attackers.
See the standard, section 184.108.40.206:
   The MAC is generated as:

      MAC(MAC_write_key, seq_num +
                            TLSCompressed.type +
                            TLSCompressed.version +
                            TLSCompressed.length +
                            TLSCompressed.fragment);

   where "+" denotes concatenation.

   seq_num
      The sequence number for this record.

Comment: The point of the sequence number is indeed to guarantee that the complete stream of bytes is correct, even if each MAC is computed only over a single record.
Comment: right, so, assuming there is no flaw in security does that ensures the integrity of whole file, if individual records of file are verified and assembled correctly by receiver?
Comment: got you, that said, individual fragments and even re-assembling sequence numbers are protected, so, that ensures complete integrity!
Answer: As in the other answers, SSL/TLS protects against corruption or tampering of the file in transit.
However, it's still possible for the file to be corrupted in memory or on disk at either end, so for critical data (firmware comes to mind, where a wrong bit could brick a device), checksumming is still a very good idea - but not a 'security' issue as such.
Comment: +1 for considering that transmitting data is more than simply following a protocol spec.  Remember also that TCP/SSL/ etc are all models.  Real code has errors in it, so it never hurts to make double check that the whole equals the sum of the parts.
Comment: That too. Hadn't considered implementation errors.
Answer: You need to have a way to keep track of order of pieces and also make sure you get all pieces. A sequence number, checked end-to-end can probably solve this. Also, you need to make sure that no piece is replayed, so you also need to verify freshness.
Comment: lets say TLS/SSL is already ensuring that replays are not happening (I am talking about ideal scenarios, it would be hard to break TLS in normal scenarios as well) and I am already assuming that there is no packet drop (please see my question)


Where to get iPhone app download statistics?

Question: I know this is a elementary question, but I figured I'd get a quicker answer here than Apple support. Where can I find out how many times the app has been downloaded and other download stats? I'm a developer and can't find the stats on the iOS Dev Center. I have not renewed the $99 Developer license, so could it be hidden because of that?
Comment: Your apps don't 'disappear' when your license expires? Interesting. Never thought about that before.
Answer: If it is the application you developed, you can access it from itunesconnect.apple.com which is called iTunes Connect, and that's how you should have uploaded your app to Apple in the first place.
You can also try a piece of software called AppFigures, which is essentially a portal to iTunes Connect, which I find easier to use and with more features.
Also: after not renewing your iPhone Developer licence, your apps will stay in iTunes Connect for some period of time, probably around a year before being deleted.
Comment: Oh, I forgot to mention that iTunes Connect only keeps 14 daily reports and 13 weekly reports at a time, which means you will only be able to see the download distribution for the past 13 weeks it was live on the store. After that you have to look at the financial reports.
Answer: "The App". Your app? Any app?
You cannot find out how many times any arbitrary app has been downloaded.
Your own apps, yes. With an in-good-standing (paid up) developer account, you will be able to access iTunes Connect, which offers some download metrics, going back thirteen weeks into the past.


Looking for a word that describes this type of strategic takeover

Question: Is there a specific word (or possibly phrase) that represents a type of takeover where an individual is planted into an organization and gains trust and respect over a period of time until he's in a position to facilitate the takeover? Kinda like an inside job from the outside?
Comment: "Mole", perhaps?
Comment: Mole, sleeper agent, fifth columnist, Manchurian candidate.
Comment: I also seem to recall that the term "wrecker" was used in soviet propaganda for quite a while towards the middle of the last century. Probably analogous to the original meaning of "saboteur", in which case both would imply working from the inside. Be that as it may neither seem to express the concept as well as mole. "Double agent" is another variation on the theme.
Answer: I think you could refer to such a person as a "mole" or "sleeper agent" without fear. In the parlance of intelligence a "mole" is used for any agent that infiltrates an enemy organization and attempts to gain their trust so as to weaken or disable that organization. Whether it's by the release of secrets, operational inefficiency, or other means, seems to make no difference. The act of weakening, disabling or destroying the organization could be referred to as "subversion".
Comment: This describes the individual, but I'm asking about the strategy specifically. Like "coup" or "mutiny" or "insurrection" etc.
Comment: It could be referred to as a "coup de foudre"; but that almost always refers to love. Perhaps "subversion"?
Comment: YES! That one (subversion)! I couldn't for the life of me recall that word. Thank you. Edit your answer so I may select it?
Comment: Done. Consider the addition of "degrade" as well. IIRC Obama has used it when speaking about his plan to defeat ISIS in the sense of "degrade their combat capability".
Answer: To describe this strategy, you may refer to entryism (also referred to as entrism, occasionally as enterism) that is a political strategy in which an organisation or state encourages its members or supporters to join another, usually larger, organisation in an attempt to expand influence and expand their ideas and program. In situations where the organization being "entered" is hostile to entrism, the entrists may engage in a degree of subterfuge to hide the fact that they are an organisation in their own right. (source Wikipedia)
In specific cases, infiltration would be another possibility.
To infiltrate means to secretly enter or join (something, such as a group or an organization) in order to get information or do harm.


Log Calabi-Yau surfaces without maximal boundaries

Question: Let $X$ be a smooth projective surface over $\mathbb{C}$, $D\subset X$ is an effective divisor. $(X,D)$ is a log Calabi-Yau pair if $K_X+D$ is a principal divisor. The complement $M=X\setminus D$ is a log Calabi-Yau surface if the curve $D$ has at worst nodal singularities. The pair $(X,D)$ is said to have maximal boundary if $D$ is actually nodal. As a consequence of Bertini's theorem, one can always find a smoothing $\widetilde{D}$ of $D$ in the same linear system so that $(X,\widetilde{D})$ becomes a log Calabi-Yau pair without maximal boundary. However, I'm interested in whether the converse is true, namely whether starting from a log Calabi-Yau pair $(X,\widetilde{D})$ such that $\widetilde{D}$ is not maximal, one can always find a degeneration $D$ of $\widetilde{D}$ so that $(X,D)$ is a log Calabi-Yau pair with maximal boundary?
Comment: Why you can always find a smoothing? The linear system is not necessarily base point free.
Answer: Firstly, I do not think that every maximal boundary has a smoothing. For example, if the linear system $|-K_X|$ as fixed part, then very likely it contains no smooth element.
On your question of the converse part, we can not expect to find a maximal boundary. For the easiest example, just consider $X=E\times \mathbb{P}^1$, where $E$ is an elliptic curve. Then every element in the linear system of $-K_X$ Is just two copies of $E$, which is smooth. So there is mo nodal boundary.
Comment: ...or an abelian surface (with $D=0$). Maybe the question becomes more interesting if $X$ is rationally connected (or Fano?).


Looking for instructive examples on how to defend against the Giuoco Piano or Giuoco Pianissimo (?) opening from Black's perspective

Question:
e4 e5 2. Nf3 Nc6 3. Bc4 Nf6 (The Two Knights Defence is my choice) 4. d3 and I am obliged to play the Giuoco Piano 4... Bc5. I am afraid of the middlegame positions that arise after this opening, because to me it seems that white is in the driver's seat being able to play anywhere on the board f.ex c3-d4 or Be3-fxe3 and then doubling rooks on the f-file or pushing a4-b4 and against all of these plans I feel lost. I can't get counterplay. I've attempted the usual operations: developing my pieces, striking in the center with the move d5 and aiming to equalize the game but it's complicated and I often end up losing the game if not in the short run then will have to endure until a blunder happens in the endgame after many moves of torture. Of course there are many other plans that white might execute but that's even worse for me.
Comment: Patience is key. The guioco piano takes a while to get going, so black does best to develop their pieces and prepare the ...d5 break carefully. I personally find it tricky as white if black drops their bishop back from c5 to b6, since this means less things for white to target in black's position. You'd do well to figure out if you prefer to play aggressively or more solid against this opening, as it affects the setups you're trying to go for in the middlegame.
Answer: <code>[fen ""]
[Event "Ding Liren - Giri"]
[Site "Wenzhou CHN"]
[Date "2017.08.09"]
[EventDate "2017.08.08"]
[Round "2"]
[Result "0-1"]
[White "Ding Liren"]
[Black "Anish Giri"]
[ECO "C50"]
[WhiteElo "2777"]
[BlackElo "2772"]
[PlyCount "90"]

1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. O-O Nf6 5. d3 O-O 6. h3 d6
7. c3 a6 8. a4 Ba7 9. Re1 h6 10. Nbd2 Be6 11. Bxe6 fxe6
12. Nf1 Nh5 13. Be3 a5 14. Bxa7 Rxa7 15. d4 Qf6 16. Re3 Nf4
17. h4 Qg6 18. g3 Raa8 19. dxe5 Nxe5 20. Nxe5 dxe5 21. f3 Rad8
22. Qc2 Nh5 23. Kh2 Rf6 24. Rd1 Rdf8 25. Rdd3 Qf7 26. Qd1 Rg6
27. Qe1 Qe7 28. Kh3 Rxg3+ 29. Nxg3 Nf4+ 30. Kh2 Qxh4+ 31. Kg1
Rf6 32. Rd8+ Kh7 33. Rd2 Rg6 34. Rg2 h5 35. Rh2 Rxg3+ 36. Kh1
Qg5 37. Qf1 h4 38. Re1 h3 39. Rd1 Qh5 40. Rd7 Qxf3+ 41. Qxf3
Rxf3 42. Rhd2 Kh6 43. Rd8 Kh5 44. Rh8+ Kg4 45. Rd1 Ne2 0-1
</code>
I think that the way Anish Giri plays the Italian as Black is very instructive.
It is also funny that White faced all the problems you mentioned having as Black in this game, and it shows how Black avoided the headaches you named.
Some ideas (I would not call them rules...) in the Italian...

I like to go ...a6 and ...Ba7 immediately and only then ...d6. It gets the bishop out of harms way so that we are more flexible in how we react to moves in the center, like d4 (because d4 does not hit the bishop anymore). And we can still retreat it with ...Be7 if that is how we want to parry Bg5 (matter of taste if you want to go for ...h6 and ...g5).
If White goes for the pin with Bg5 before Black has castled kingside, we go ...h6, ...g5 kicking the bishop and we may go for a kingside attack (even after we castle kingside outselves!). A useful maneuver to enable a pawnstorm is ...Nf6-h7 supporting the g5 pawn to play ...h6-h5 (once we are ready).
If White does not go for Bg5 early and plays slowly, a good plan is ...h6, ...Re8, ...Be6 and then ...Rxe6 after the bishops are swapped. The rook may stay on the 6th rank or reatreat back to the 8th.
If White goes for Be3, swapping there is usually okay if we have not played ...h6 yet, as ...h6 weakens squares around our king and we might get crushed after a sacrifice. But you never really have to take and while the rook may look bad on a7, it is not as far from the action as it may seem (see the game I posted).

You will still learn some common mistakes by White, like mistiming d4, leaving f2 vulnerable and others. Another thing to look up is how to deal with unsound sacrifices on f7 or g5 (after ...h6, ...g5 White very often plays Nxg5, but it mostly is not sound).
You also need to look for active play. If White's move seems very slow, or his forces do not look fully coordinated, you might have an opportunity to seize the initiative by striking in the center or on the kingside (mostly). If you look at the game I posted, it is not clear where the initiative of Black came from, but it crushed.
Comment: Thank you very much! This was a superb reply.
Answer:
... Bc5 isn't your only option.

Both MCO-13 and ECO C[55] (1981) list 4. ... Be7 as the main continuation. In the notes, ECO has h6 as an option, or d5, transposing to a line in the Bishop's opening (C24), after 5. exd5 Nxd5.
Comment: It's not the only option, but it's the best move after 4. d3. Be7 is passive and unnecessary in comparison to Bc5.
Answer: https://old.chesstempo.com/game-database.html
Nxe4 has a 100% win score from that position based on players 2200 up to 2400
at 2500 - 2700 BC5 has best results  although about 9% worse than whites result
what level is your opponents at ?
Personally I play BC5 and gladly let the Max Lange happen.  You might want to memorize that one if you let them play that one as it is complicated.
OTOH  The sicilian stops the Giuoco nonsense.  So do many other first moves 1... pd3 is good for black too.
Comment: I don't understand. You are recommending to answer 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.d3 with 4...Nxe4? That "100% win score" must be for White, but I doubt Nxe4 has ever been played above beginner level. Also, after 4.d3 Bc5, the Max Lange is not going to happen.
Comment: Did you even read the question? OP is asking about a lline where White played **4.d3** protecting the e4 pawn with a pawn. Nxe4 simply loses a piece.
Comment: Look at chesstempo link and see the 2200-2400 players winning 100% with that move as black.  See also the 2500-2700 players wining 9% more for white.  You can doubt all you want but the data is there from actual games showing you are wrong.   True the lange wont happen there after pc3  but it happens a lot and is not to be feared by black.
Comment: Wow.  A true provable statement and the kiddies downvoted a totally correct answer.  WTF?!
Comment: @bof    did you look at chesstempo game database and see the actual results by masters ????  Or are you ASSuming that you are so much better that the move in that database is wrong.
Comment: I looked at the database. In the position after 4.d3 the only moves played by Black were Bc5 (#4820), Be7 (#4200), h6, d5, d6, Qe7, Bd6, Bb4+. Nobody ever played 4...Nxe4 in that position, probably because it's refuted by 5.dxe4.


Problem with scrum master and developer role?

Question: Can the scrum master be a programmer on the team and take the role of scrum master just for now?
As is done in the time you must make a plan?
Answer: Technically yes, they can. Unlike Jesse, I don't have any preset preference whether the roles should or should not be mixed. I would more look at the context and current team's needs and then decide whether you need have your Scrum Master (SM) full time or not.

If the team is new with Scrum an experienced person acting as SM is: one, a very good idea and two, will have a lot of work coaching and mentoring the team. In this case I'd probably tend more into exclusive SM role.
However, if we take the same situation but have no one experienced is Scrum you may want to reconsider. I mean there will be as many questions as in previous case although inexperienced SM can be way less helpful, rendering the idea to have him as an SM full-time not so wise. In this case I'd likely have the roles of SM and developer mixed and look for some support from outside of the team.
If the team is mature and they are fluent with Scrum there's usually significantly less work for Scrum Master, which means there will be probably quite a lot of spare time between different SM's tasks. In this case I'd either have a single SM working for more teams or assign SM other tasks, e.g. development.
If the team is small, e.g. of 4 people, you probably don't need SM full-time even if people aren't experienced in Scrum. There just isn't enough work for such person. In this case I'd act depending on the context: I might use experienced SM in different teams or have them working on development. If my SM is inexperienced I'd probably have them working on development.
As team grows there's also more work for SM. Naturally coaching and mentoring tasks scales up with the number of people. Also bigger team usually means bigger throughput which means longer meetings (planning, retros) to facilitate and more time needed to prepare to such meetings. With a bigger team you may end up needing SM closer to full-time. Note: Scrum teams (most teams really) don't scale up well beyond 7-8 people so you may prefer to have two smaller teams and a single SM working for both.

In every case remember: some experimentation will definitely be helpful. Start with one approach, see how it works and don't be afraid to change it or tweak it to see whether another setup isn't better. You will also notice that situation changes over time and you should adapt to it on organizational level, which means you might want to change your approach over time.
Answer: Yes, this is possible, however ideally I personally believe the scrum master role should be a dedicated role per sprint. If developers want to pass around the role of Scrum Master on the team that is fine.
If you want to "dual role", there some some pitfalls to be aware of:

Don't let your development duties take precedent over scrum master duties. As the scrum master it is your responsibility to ensure that your team's hurdles & road blocks are being removed. Don't neglect that because your busy constructing software.
Don't over commit the team within a sprint. As you are the scrum master be aware that you are the teams facilitator and may get busy over the course of the sprint and "neglect" a dev story that you picked up.
Don't let the fact that you are the scrum master, take precedent in team discussion and planning sessions. Just because you are wearing two hats doesn't mean you have "two votes" on a team discussion
Answer: Yes, there is nothing to prevent a programmer from being the scrum master.
When one of the programmers on the team taks on this role it is important for them to have a good appreciation for the amount of time that they will be committing to the role.
If they are doing it full time it is important that they don't assign any tasks to themselves.
If they try to do a 50/50 split give them the time to find out if they are allocating enough time to themselves to do their development tasks. A good way of checking this is to have regular post-mortems after each sprint.
Answer: Totally do-able, but consider the maturity of Scrum in the team.
I started exclusively as a Scrum Master and helped spin up Scrum in our other IT teams (PC\Service Desk/ systems/ network/ and worked with our GIS group too) over the past year. Our AppDev group has been practicing Scrum for about a year and a half longer than these newer teams and are a bit more mature.
At first, these new teams consumed a lot of my time. I worked to help solidify our PMO and create repeatable practices and consistent project delivery. While business and internal IT projects still have some maturing, I can easily manage 2-3 teams and take on work coaching other business units interested in Scrum, manage a small waterfall project (usually a vendor facilitated project) and perform work with our business process analysts. The goal, as a Scrum Master, is to teach your teams to self manage and work yourself out of a job and really only get tagged in when big impediments arise.
So what does one do? My self, I really enjoyed development in college and do it as a hobby. So I negotiated with my management that I want to get back into development and sharpen my technical skills but will also fill in as a SM for 1 mature team that I don't work in.
They hesitated, but I was honest. Told them I felt a little bored and didn't want to leave the organization because I wasn't feeling challenged or lose technical skills. Just remember to know your limits, be coachable (just like our great teams), and spread enthusiasm and commitment to excellence and business agility.


Identifying unusual wild raspberry plants?

Question: I am located in Southwestern Pennsylvania and I know wild black raspberries are native to me and the surrounding counties. The plants are randomly growing in patches throughout the woods on my property which tells me they were spread by bird droppings. Primocanes reach about 8ft long and the floricanes are a deep purple color. Floricanes are not pictured. The canes are a bluish white (glaucous) color, the cane is smooth/round and not angled/squared like some wild blackberries, whitish underside of the leaves, and tip rooting. These are all common black raspberry traits. However, I have never seen the canes flower/fruit. This makes me wonder how they spread so randomly if it was from bird droppings. No fruits = no bird droppings. I am uncertain that these are black raspberries (Rubus occidentalis). Is there such a thing as a non fruiting rubus-looking plant? If they are black raspberries, they must be a late bearing variety.
Answer: You mentioned they are growing in the woods, which means they are in at least partial shade. Raspberries (like many fruit-bearing plants) will only produce fruit if they have adequate sunlight. It's quite common to see wild-growing raspberry patches that don't fruit, because they don't get enough sunlight.
Somewhere else, there is a patch of raspberries growing in the sun. Those plants make fruit, birds eat the fruit, and deposit their seeds in many places. Some of the places where the seeds are deposited, have enough sunlight for the seeds to grow into healthy plants, but not enough sunlight for those plants to make fruit.
It's also possible that the patches are not bearing fruit because (as blacksmith37 mentioned) they are diseased. A disease can cause a plant enough stress to prevent it from fruiting.
To summarize: it's not a non-fruiting variety of raspberries. It's simply a patch that doesn't have enough energy resources to produce fruit this year.
Comment: The photos I was able to gather are from the patch with the most sunlight. Other patches are in the shade from the dense woods. I am going to try an experiment and transplant some of the healthiest canes I can find. I will place them in some good soil and provide ample sunlight. Black raspberries are at the top of my berry list in terms of flavor (even ranking higher than Cloudberries). Maybe I might be able to harvest some black raspberries next year.
Comment: I strongly recommend doing some research into the kinds of diseases raspberries can get. I've heard of people having to destroy entire raspberry patches because of disease (some kind of rust fungus in that case, if I recall correctly). Even apparently healthy canes had to be destroyed in order to eradicate the disease.
Comment: Also, I totally agree with you. Black raspberries are the best. It's always disappointing when the wild black raspberries start to go out of season, and the wild blackberries come into season. Wild blackberries are just not as good. But have you ever had [wineberries](https://en.wikipedia.org/wiki/Rubus_phoenicolasius)? They're almost as good as black raspberries. They're invasive so you shouldn't plant them, but by the same token you can feel virtuous when picking them in the wild. Every berry you eat is one less that will be planted elsewhere by birds.
Comment: Yes I prefer black raspberries over blackberries. I am eager to try the purple raspberries and Tayberries that I planted this year. I have at least 100 wild Wineberry plants on my property. The taste is good but not the best in my opinion. The birds love them and it seems like the Wineberry seeds sprout very easily based on the random Wineberry plants popping up everywhere.
Answer: The photo of the vine tips seems to show some are dying. This is typical of black raspberries, they are highly subject to anthracnose mold. The main task when growing black raspberries is removing any diseased parts to slow the spread. It can prevent fruiting if severe. They mostly spread by new canes touching the ground and rooting
Answer: It's either that, or whitebark raspberry


Whatsapp Profile Pictures folder missing

Question: I have a peculiar scenario with the Whatsapp Profile Pictures folder. Previously the Profile Pictures of contacts which I view used to get stored inside Whatsapp Profile Pictures folder. One day an error message (I presume) got popped up and I pressed OK without reading the message. From then the folder went missing but I am able to view the pictures even if the mobile is offline. Don't know where it is now saving the images. I have also checked if the folder was hidden. Even if I recreate the folder it is not storing the images in that folder. I have also reinstalled the application. Does whatsapp store the images in any other format or location other than storing in the default folder.
Answer: WhatsApp no longer caches/stores the viewed profile pictures under /sdcard/WhatsApp/Profile Pictures/ directory, due many reasons, like this..Now, it's stored under its own app cache area in /data partition.
If you're rooted, then head over to the directory: /data/data/com.whatsapp/cache/Profile Pictures/.There, you'll find the cached profile pictures (that you have viewed).
If you're not rooted, as others have said, you need to explicitly save the profile picture from the WhatsApp app by clicking the pic, click again to enter full screen, click the 'Share' icon and press 'Save to Gallery'.
Now the saved profile picture can viewed in the directory: /sdcard/WhatsApp/Media/WhatsApp Profile Photos/
Comment: Sharing user photo saved it in whatsapp images /sent/ folder for me
Answer: I think I have exactly the problem (except I don't recall getting any error message), the folder in Whatsapp\Profile Pictures is just gone. What I've figured out is that now you'll have to manually save a contact's profile picture, i.e. after the picture is loaded, you'll have to keep pressing on it. It'll open up the picture and then you can save it. It'll be in Whatsapp\Media\Profile Photos. Hope this helps.
Answer: When you open the Profile picture of any person in the WhatsApp; you will able to see the Share symbol at Top - Right of the screen.
Click on it and you will be asked to share with lots of Apps; but at the top you will have "Save to Gallery" -- you can select this option and the Profile picture will be saved in the folder --> media >> WhatsApp Profile


What is the difference? "Adding more LSTM layers" or "Increasing epochs"?

Question: To get more accurate results which one is better? Adding more layers or increasing number of epochs? I like to know the difference between effects of these two approaches?
Answer: Increasing the number of epochs :
This is the best when you have a large and diverse dataset. A large dataset refers to a number of diverse samples in equal amounts ( no bias ). Also, you make your model generalise better, you might increase the dropout rates and decrease the learning rate. At such a time increasing the number of epochs would help the model generalise better. Also, since it has generalised on a diversed dataset means it can perform well in the real world. For LSTMs, they can make correct predictions based on the sequences.
Increasing the number of layers of LSTM :
If we treat each LSTM as a memory unit then we are increasing the number of memory units and thus the overall memory. The first sequences would be feed to the next layer hence a model could create a hierarchical representation of the data. This is better if you have sequences which have such a context like an image.

On considering both the scenarios, if you have abundant data then the first option is optimum. If you have complex data which has less diversity then the second and the first points need to be considered.
Comment: How can I play with learning rate in Keras.LSTM?
Comment: I referred the learning rate which is initialized with the optimizer in the `fit()` method of your model. If you are using an RMSprop optimizer for your model then `model.fit( optimizer=keras.optimizers.RMSprop( lr=0.0001 ) , loss='categorical_crossentropy' )` where `lr=` is the learning rate.


Why did Sam join the Night's Watch

Question: Sam's father wanted to get rid of him so his younger brother could become the heir; he threatened Sam and forced him to join the Night's Watch. Ok, fine, but I have some problems with this. First: why the Watch? Given that Sam was a bookworm, if would've made much more sense to send him to the Citadel; this would also achieve the same purpose since Maesters forgo any claims and titles. Second, given that Sam had "chosen" to take the black out of free will (i.e., he wasn't a criminal), couldn't he just say he changed his mind after arriving on the Wall and so leave (before taking his vows, of course)?
Answer: You may have missed that Sam had already explored the option of becoming a maester with his father. The result was that Lord Tarly said something to the effect of:

If you want to wear a chain, so be it.

...And chained him in the dungeon. Lord Tarly is a hard man, and has been trying many different things to make his son into what he wanted him to be. Allowing him to become maester would not be something he wanted.
As Sam says in AFFC/ADWD, the life of a maester is servitude, and no son of Lord Randyll Tarly could humiliate himself in that way. In the Night's Watch, Lord Tarly figures that Sam might finally become the hardened man he always wanted him to be. Although I don't think he really cares, he just wanted him gone, so his younger son Dickon could be his heir.
Finally, of course, Sam cannot exactly leave the watch. As long as he is alive and a free agent, he threatens Dickon's inheritance, so Lord Tarly would probably have him killed.
Comment: I think it doesn't matter to his father if he leaves the Watch or not. Aside from being an embarrassment, I think it wouldn't change anything. The way I understand it, the oath is binding. Which would mean, once he has taken it he has forfeited all rights he once held and is no threat to his brother. Not to mention he will be hunted and executed because he is a deserter and would hardly be able to find enough support to cause any trouble.
Comment: Well, your point is moot. If he leaves the Watch after taking the oath, his life is forfeit, so he cannot inherit anything. If he leaves it before taking the oath, which is what the OP meant IMO, then his father will kill him, just like he promised to do in the first place.
Comment: @Elemememore If Sam was brave and adventurous he might try that, but he isn't. He would be alone and without money, since he no longer has his Tarly name and wealth to rely on. Oldtown is not far from his father's lands, and he would not live long there.
Comment: Taking the black voluntarily is also seen as the final means of redemption, the last way to save one's honour (not to mention the family's).
Comment: @MPelletier Yes, but I don't see what you mean in this case.
Comment: It's just another argument in favour as to why Sam would join the Night's Watch.
Comment: Afraid I still don't get your point in this context... Sam was forced to join the Watch.
Comment: @TLP Yes, he can leave before taking his oath! Sure, his father would probably want to kill him in this case, but I doubt he has a whole network of assassins ready to kill Sam if he left the Wall. I don't see why he couldn't just leave and start a new life somewhere else. Or maybe find a way to Oldtown to become a maester, in which case he would probably be safe.
Answer: Sam's father wanted Sam to disappear, and if that meant death, so be it.
In fact, I believe that was exactly the choice his father gave to Sam: take the black, or risk dying in a hunting "accident".
The life of a Maester is a relatively soft, easy life, and Maesters live to a very long age.  Life on the Wall, on the other hand, is hard and dangerous, and many don't survive the first few years.
Sam's father was hoping Sam would die quickly, without leaving any blood (figurative or otherwise) on his own hands.  Killing your kin is one of the biggest taboos in Westeros, but it doesn't prevent people from wishing their own kin dead, or even trying to bring it about indirectly.
Comment: Later we learn that Sam's father also despised the thought of his son becoming a Maester. I think it was something like "no son of mine will wear chains"
Comment: A long-lived Maester would be around to cause trouble (or embarrasment) for quite a while too.  Not only Sam's father want him gone, but he wanted him gone *fast* and *forever*.
Answer: Sam's father hated him and the man he might become.  His father has a reputation as a seasoned warrior with successful battles to his credit.  Seeing Sam lay about reading with his mother and living a life he thought was not masculine in its tone is something Tarly could bear.
Sam's option was leave or be killed in a hunting accident.
Comment: This doesn't answer the question at all.
Answer: I'm not at all sure this is backed up by the books, but perhaps House Tarly, being Targaryen loyalists (well, they used to be anyway), are anti-Citadel.
After all, the Maesters spent centuries plotting and putting in motion the demise of the Dragons and of House Targaryen. And perhaps House Tarly is aware of this fact, or even just vaguely aware of it. If that's the case, Randyl would not want the Citadel to have what is somewhat of a hostage or double agent.
So - better Death than Maestership for any Tarly!
(This might also have something to do with House Hightower, but that's too speculative and out there so never mind.)
Comment: You need to back this up with canon evidence, I've never heard this "Maester against the Targaryen rule" theory
Comment: @Edlothiad: Haven't you listened to Marwyn? And don't you remember the Hightower involvement in fomenting the Dance of the Dragons?
Comment: "He suspected". That's not evidence
Comment: @Edlothiad: "The world the Citadel is building has no place in it for sorcery or prophecy or glass candles, much less for dragons."
Comment: Said by the same guy who ran off to help the last targaryen queen, you can believe what he says. I'm not taking that to mean the Citadel killed the dragons, we'll have to wait for the new book to confirm it.
Comment: @Edlothiad: Marwyn was being critical of the "world the citadel is building", so it's at least consistent. Now, ok, he could be just making stuff up to justify his own actions/outlook, but then - almost all of early Westerosi history could be just a bunch of fairy-tales.

Why did Sam join the Night's Watch


Tails 1.2.2. "Could not determine whether an upgrade is avaiable from our website"

Question: For about 4 or 5 days I have received this error message every time I have started Tails.
I have restarted, changed computer, created a new USB with a new ISO image but still get the error message. Is this something to be worried about or does it relate to the forthcoming manual upgrade to Tails 1.2.3. ?
Comment: I've entered this as a comment because I am not absolutely certain ... but, I think you have guessed correctly. The security certificate for the Tails download site is about to expire, which was why version 1.2.2 was released when it was; i.e., so the certificate relevant to the 1.2.3 upgrade could be downloaded and verified (with 1.2.2) before the expiry of the old certificate. So 1.2.2 would now have a certificate that does not become relevant until 3 Jan 2015. Hence the apparent error message. I should also say that I receive the same message having upgraded from Tails 1.2.1 to Tails 1.2.2
Comment: That problem should be fixed now since the new certicate has already become valid. Do you still experience the error @Mabuse ?
Answer: It was an issue with Tails' update mechanism that has since been fixed. It shouldn't have happened since then, if it did please let the Tails developers know as soon as possible


Developer questions

Question: Are questions from developers about, for example, writing a routing daemon on topic?  I'm thinking specifically about question like internal application processes rather than how the protocol works.   The on/off topic list is silent on this matter.
Answer:
Point of order: Although I'm a pro-tem moderator here, this answer
  has no special weight/meaning. I urge all the comm members to vote
  their minds, and if someone disagrees/has-a-better-idea, please post
  your answer(s) too.

Maybe...
On Topic: questions about the protocol design and features. The Net Prot design/theory I think would cover this.
Off Topic: questions about how to write the software to implement network protocols. Other examples of off-topic programming material: how a programming / kernel network API should work, or how to use a programming / kernel API.
Stack Overflow is the place for all programming and API questions.
Comment: I was aiming for a more generalized form of the question, rather than that specific post.  I guess I don't have the same visceral reaction to code jockeys as you. ;)
Comment: I am sympathetic to and appreciative of the amount of work you have put into this site.  Perhaps we can deal with this by simply deciding this question.  Programming questions, e.g., how to design or code network protocol functions in applications or utilities are off-topic. If it's policy, then we can point to it and be done.   If no one (else) feels strongly enough to vote yea or nay, then we can make policy based on our votes.

Developer questions


Gmail accessed by third party - deleting important emails - saw one disappear an hour or two ago need recovered

Question: I am in a custody dispute and my ex has in the past verified used spyware - very resourceful.  I noticed on multiple occasions that key emails were deleted - a few times I managed to recover them and they were basically all important to one person only.
I was just looking at an important email a few hours ago, clicked away from it and returned 30 seconds or less later to find it gone and not in any folders,  I checked trash spam etc, and nothing.  I then went to https://support.google.com/mail/workflow/9317561?visit_id=637158719326521936-227949149&rd=1 (Gmail message recovery tool) and made request for recovery.  Returned message to check my email - if found it would reappear within 20 hours.   I remembered that one time before it had taken a few hours, so checked back and still nothing, so I tried again. this time it returned "were sorry no messages to recover, tried again and it returned "we see you have a recovery in progress - continue or start new"  i cant recall but it returned various messages each time, one of which was "something wrong, escalate with google - only came up once - now returning nothing or "we see a search is requested, continue or new"
I think google can search - ie with a person doing it on their end for 30 days - not sure how to escalate though. And yes I have changed PWD multiple times - HELP
Answer: Use Google Feedback.

Go to gmail.com
Click on the gear button then click Send feedback
Fill up the form and submit it.

Also post a question on the official Gmail forum -> https://support.google.com/mail/community


What does the name "Red Heat" mean?

Question: Many of you heard of the movie "Red Heat" with Arnold Schwarzenegger as a star.
Russian distributors translated the word "heat" into Russian in its main meaning, i.e. hotness, warmth. Along with that some dictionaries say that one of the meanings of heat is police, so the most appropriate name of the movie in Russian could be "Red Cop". This point of view is controversial according to discussion on Russian Wikipedia. I would like to know opinions of native speakers.
Comment: I've never watched the movie, but "heat" is slag for "police" in American English. "heat" can also refer to a situation where things get a bit intense. For example: "If you can't take the heat, stay out of the kitchen".
Comment: We can only tell you the possible literal meanings of the words. Anything beyond that is lit-crit in miniature, and off-topic.
Answer: The title is a play on words.
"Red hot" refers to iron or steel that has been heated until it glows red. Metaphorically, it has been used as a superlative, e.g. "the last of the red hot lovers." In that metaphorical sense, "red hot" means "very exciting."
The primary meaning of "heat" is degree of hotness or warmth. It is also an American slang term for the police.
The primary meaning of "red" is a color, but it can also mean "communist" as either a noun or adjective.
Because the movie is about a Russian policeman while the Soviet Union still existed, the primary but allusive meaning of the title is "Soviet Police," but because of its closeness in sound to "Red Hot, it also suggests "Very Exciting." I know no Russian, but I suspect that kind of multiple meaning is untranslatable.
Answer: Red = Russian/Communist.  Heat = Police/Pressure.
Red Heat = A police movie involving Russians.
Comment: For bonus points, please describe why Blue Crush has to do with surfing.  Blue = Ocean/Sea  Crush=surf board wipeout.  Blue Crush = Movie about surfing on the ocean, possibly involving a serious wipeout.
Answer: When a substance is heated it can reach a state in which it glows red. This is called "heating the substance to a red heat".
That is the literal meaning of the phrase.
We can also exaggerate and say that something is red hot, even though it is not literally glowing red:

Careful, those muffins are right out of the oven. They're red hot.

And it can be used to mean "on one's game, performing with great skill or great luck":

I've won six straight poker hands. I'm red hot tonight.
Comment: I think "Red Heat" is actually a welding term.  "Red Hot" -- commonly used to describe something very hot.  "Red Heat" -- If you're not holding a welding torch, you're probably not going to hear or use the term "Red Heat".
Comment: "red heat" is indeed a term used by welders.  I've taken a welding course and do some welding now and then :)  But it is not only a welding term, as the link above will show.
Comment: The link above returns a bunch of welding sites.  I think it's almost entirely a welding/technical term, not used in general conversation, and without cultural references.  When you say, "red heat," someone, in their mind, must convert it to, "red hot."  Sentences like, "The red heat really got to me," will not be understood.  Red Heat does not mean Red Hot.
Comment: EllieK: You're not a very careful or thorough reader. "several large stones are heated to a red heat". We don't weld stones. And I never said "Red Heat" means "red hot".

What does the name "Red Heat" mean?


How to record sound from digital keyboard to computer?

Question: I'm trying to record my digital keyboard/piano (Yamaha) onto my laptop (Hp) and I've looked all over online, YouTube, downloaded various software programs, etc., and I can't find out how... thanks!!!
PS, also what are some of the best software programs (other than garageband, because it only works on mac) to use to do this? Thank you so much!
Comment: Is this an electric piano that you want to record via the cable, or a piano that you want to mic up?
Comment: its an electric piano, yes, I want to record via cable
Comment: what model is it?
Comment: it says it's a Yamaha portatone electronic keyboard
Comment: There are lots of 'portatone' keyboards. The exact model number would help.
Answer: Recording a keyboard needs the following things - an audio interface, a pair of high quality headphones, a computer and a keyboard.
There are different audio interfaces available to choose from. To give you a list of the same would include the following:

Presonus AudioBox USB {2X2 Interface}
Roland Duo Capture {2x2 Interface}
Focusrite Scarlett 2i2 {2x2 Interface}

Once you have a suitable audio interface, you can connect the keyboard from its audio output jack to the audio interface's input and then connect the USB out from the interface into a USB jack of your laptop. To monitor the sound, you must connect the headphones to the interface (and wear them).
Talking about softwares, there are loads and loads of free ones that will work in your case with ease. Here's list of some:

Audacity {Free & most easy to use}
Presonus Studio One {Recommended to use with the Presonus AudioBox USB Interface}
Adobe Audition {NOT FREE but also a very easy to use and preferred software}
Cubase LE {Paid pro software}

If you don't wish to go through this way, then there's another easy and free way to record your keyboard. Connect the keyboard via USB directly as a midi keyboard. Then you have to download VST plugins from VST4Free.com and using a software like Cocos Reaper or Nuendo, you can record tracks of your performance. However, the sound will not be that of your keyboard but that of the VST plugins you download. This method is not very fruitful unless you have professional VSTs (which need money). To record your own keyboard, buy an interface and make your studio setup.
This is to sum up how to record a keyboard on your laptop. You will have to go through several tutorials and failed audio production attempts before you can successfully get the best recording of your performance. Good luck with it.
Answer: I think that keyboard has midi out so you could buy a cheap midi to USB adapter and free midi software like http://midieditor.sourceforge.net/.


Pronunciation of the word 'infantry'

Question: I didn't have any doubts about this word, because as I could see it is pronounced in both British and American variants as [ˈinfəntrē] - as it written - and I heard it in modern military usage sounding like that, until I heard an American WWII song The Ballad of Rodger Young  in performance of West Point Cadet Glee Club - and it occurred to me, that they definitely pronounce it like 'enfantry' https://www.youtube.com/watch?v=1MEJM0cboDg#t=7 Then I searched some other variants of the song - and in the most of them the same pronunciation was used, although in some not. Then I have searched the Internet and have looked up in dictionaries, but nowhere this question was discussed. I think that maybe this is the variable pronunciation like insure/ensure, inquire/enquire, or dated, or dialectal, or specifically U.S. military, but still cannot find any arguments in favor of anything. Or is it just a personal accent of the singer and nothing interesting?
Comment: Also, what do you mean "it is pronounced as it is written"?  Nothing in English is.  For example, where is the *‑chree* you would expect to find in the written word if it were "pronounced the way it is spelled'?
Comment: I'm not as  convinced they are saying `[ˈɛɱfæntri]` as you seem to be, but do please keep in mind that when spoken, *the infantry* is phonemically `/ðiʔˈɪnfəntri/` — but that when sung, you cannot stop the glottis. So it all runs together.
Comment: I've heard 'infantry' pronounced (especially as an attributive noun) with no stress.
Comment: @EdwinAshworth I wonder how that would work, to have no stress in it at all. So for *"an **infantry commander"*** or *"the commander of an **infantry brigade"***, are you saying that you've heard *infantry* in those uttered with no stress at all? Compare ***orange** peeler* with *orange **peeler***, or ***baby** food* with *baby **food***, or ***giant** killer* with *giant **killer***. In the noun-adjunct cases, it receives normal stress, but in the adjectival cases, it does not.
Comment: @tchrist I'm using this sense given by AHD: stress 2b. The emphasis placed on the sound or syllable spoken most forcefully in a word
 ... I hope you don't mind.
Answer: Choral performances (as in the case of a glee club) are not good sources for verifying issues of pronunciation, because it is commonplace in choral performances to alter pronunciation of words for musical reasons.  One of the substitutions commonly made is to replace an initial "i" sound as you cite. The reason is that the "i" sound in "infantry" is pronounced with a small opening of the mouth, and as a result doesn't carry well in some rooms, while the "e" sound is pronounced with a much larger opening of the voice, and has more power and carries better. The short "i" sound is also much harder for an ensemble to tune as precisely than a short "e" sound.
In the case of the word "infantry", if one happened to be were listening very closely to a live performance, from the back of a large room (and perhaps one without very good acoustic characteristics to begin with), and heard a performance with "infantry" pronounced in with a short "i", the sound of the ensemble would seem to fade a bit on the "in" syllable while it would not if the vowel sound was modified as you noticed.
By the way, my credentials on this are that I sang in a professional quality ensemble for a number of years, and the substitution of short "e" vowel for a short "i" was such a regular occurrence that it was noted when we were not to do it. Not all choral conductors will make this modification, and some will make it only in some circumstances, for example, a particular ensemble, or a performance in a particular room. I would also note that this is a bit of choral technique, and may not (need to) be used by solo voices.
Comment: Your leading clause is important and accurate: "Choral performances are not good sources for verifying issues of pronunciation."  Many phonetic modifications are routinely applied when singing, especially in a choir. Furthermore, although West Point is in New York, many cadets are from the South or are speakers of AAVE (or both), and might therefore be subject to [the notorious *pin–pen* merger](http://dialectblog.com/2011/04/17/pin-pen-merger/), and this might require extra effort to get a unified sound out of a group with different habits.
Answer: The pronunciation [ˈinfəntrē] is the right one. But it can be heard as infantri in some accents because of the sound similarity between [ə] and [a].
Comment: I think he is bothered that he thinks he is hearing the first vowel as `ɛ` instead of as `ɪ`.
Comment: Yes, it is precisely the point about the beginning of the word, although I wasn't sure is that /ɛ/ or /ə/, but not the clear /ɪ/.
Comment: So you disagree with the experts at Oxford Advanced Learner's Dictionary, who only accept this form: **infantry** noun
ˈɪnfəntri [US]  ; ˈɪnfəntri  [UK]  ?
Comment: No, of course, I don't think, that my knowledge of English is better than qualification of British linguists. I just wanted to know, why this particular example deviated from the standard pronunciation.

Pronunciation of the word 'infantry'


What is the advantage of setting a character column as VARCHAR(32) over VARCHAR(255)

Question: What is the advantage of setting a database column VARCHAR(32) over VARCHAR(255) even though the two of them consume 2-byte memory?
Answer: You are probably defaulted to CHARACTER SET utf8 (or utf8mb4), in which case (255) would need 2 bytes for the length.
But the real problem is with temp tables (pre-8.0):  If the SELECT is so complex that it needs to generate a temp table (eg, for sorting), it will try first to use a MEMORY table.  In doing so, it will turn VARCHARs into CHARs, thereby taking 765 bytes (if utf8).  If, in doing so, this (and other actions) take too much space, it will switch to the slower MyISAM for the temp table.  See the status value Created_tmp_disk_tables.
For SSN, country_code, zip, etc, explicitly say CHARACTER SET ascii (or latin1).  This will avoid extra bloat for the charset.
For fixed-length columns, use CHAR, not VARCHAR.  So, if this is a US SSN, shouldn't it be
SSN CHAR(11) CHARACTER SET ascii  COMMENT 'example: "123-45-6789"'

In spite of all that, the performance difference will be minor.
More important in the serious legal implications (in the US) if your computer is hacked into, and you lose sensitive info such as SSNs.  The cost of such a breach could bankrupt your fledgling business.  And no, simply encryption won't suffice -- think about how easy the hacker can find the encryption key.


Multi Language support for QGIS python plugin

Question: Is there any method for python plugin in QGIS 2.8 to support multiple languages.(including .ui files that is call from this python).Please anyone can help i am new to this environment
Answer: From what I understand, you are trying to support internationalization in a plugin you are developping. It is possible, although not very well documented. Please have a look at this answer which contains relevant information and links : https://gis.stackexchange.com/a/176200/64955.
In short : the best way is to look at other plugins. You have to create a .pro file in a i18n directory, then use QT 4 Linguist to provide your own translation (this will create a .ts file), or (alternatively) manually create a .ts file. Finally, run lrelease to generate a .qm (compiled) file.
If you edit your plugin (either .py or .ui files), you will have to run pylupdate4 to update the .ts file, then lrelease to update the .qm file.
Additional link : Internationalisation of PyQt4 Applications.


Jaxx transaction stays on pending confirmation

Question: Last night I tried to send ether to an address from my jaxx wallet. But seems that the fee which I set (80000 gas limit -> 10 Gwei) is very low and the transaction stayed in pending status for over 10 hours. Can I somehow cancel this from the jaxx wallet and resend it - I don't see such a button. Or to restore my wallet to MyEtherWallet and try to resend the transaction with bigger fee from there. If the second is completed is the first will be cancelled automatically when there are no sufficient funds once it is tried to be sent some day in the future.
Thanks for your help,
Georgi
Comment: I am having the same issue with mine since yesterday. I was never asked about any gas, I just approved what they requested as payment. Same issue , still pending ...
Answer: Check out this answer, as it should apply to Jaxx as well:
https://ethereum.stackexchange.com/a/35207/20276

What you want to do is re-submit your transaction, using the SAME nonce as before. As long as your transaction has not already been confirmed on the blockchain (make sure of this FIRST), then just about any Ethereum client (Jaxx included) will pull the same nonce value dynamically from its blockchain provider and simply override the previous transaction.


How do I prove that a certain price is price of European option in Black-Scholes framework

Question: I want to show whether the following price at t is of a european option in Black-Scholes Framework. $$S_tlog_e (S_t^3)
$$
Is it just trying to substitute the function (and partial derivates) in the Black-Scholes PDE?
Answer: Yes it is actually just substituting it into the Black Scholes PDE. If the PDE is satisfied, $V(t,S(t)),t\ge 0$ is a martingale and hence $V(t,S(t)) = E_t (V(T,S(T))$ so that $V(t,S(t))$ is the expected value, at time t, of an option that pays $V(T,S(T))$ at time  $T$. Here I assumed $r=0$ for simplicity
Answer: If it was a solution to a European option PDE pricing problem, at time $T$ you have $V(T,S) = S \log{S^3}$.
Based on this terminal function, you can then solve the BS PDE using a semi-analytical approach to find $V(t,S)$. My guess is it will not be the candidate you posted (haven't checked).


When Did Prophecy End For The Non-Jews

Question: In the Torah it says Bilaam was a prophet, also was a non-Jewish prophet receiving true prophecy, also would a genuine non-Jewish prophet that created his own religion, would that religion be true, but it doesn't say anywhere in tenak when prophecy ended for the non-Jews
Answer: Note that the talmud says in Yoma 69b that our prayed for the destruction of the yetzer hara for avodas zara. However, in order to counterbalance this, nevua was also removed from the world. As we discuss in Why did God created physical impulse towards the "wrong" women the impulse within man is required to give him the energy to act. This can be for good or for bad. Thus, removing the impulse to worship idols also removes the impulse to dedicate oneself to Hashem. That is why, when the yetzer hara for avodas ara was removed, nevua (true or flase) ceased. In fact, one can claim that this is the point at which the yetzer hara that we call atheism entered the world (as a general situation). However, that is a different discussion.
Thus, once Micha became the last navi, any possibility of nevua among the goyim also disappeared.
I should point out that any neviim among the goyim would not be mentioned unless they had something to do with Bnei Yisrael and the Torah needed to teach a lesson regarding them (as with Bil'am or qas the medrash says, Iyov). We know of 48 neviim among Bnai Yisrael and the talmud tells us that there were large numbers of actual neviim that we do not know (as many as left mitzraim).
From Bava Batra 15b:

Seven prophets prophesied to the heathen, namely, Balaam and his
  father, Job, Eliphaz the Temanite, Bildad the Shuhite, Zophar the
  Naamathite, and Elihu the son of Barachel the Buzite.

While there could have been more, we cannot know of them.
Among the gentiles, why Job and Bilaam were recognized as prophets whereas Muhammad was not? states

Because of Bilaam's wickedness, as emblematic of the wickedness of
  gentile prophets, God removed prophecy from the gentiles (Midrash
  Tanchuma, Balak, siman 1).

You also ask a second question that is on a totally different topic.

would a genuine non-Jewish prophet that created his own religion,
  would that religion be true

If the new religion contradicted the Torah or attempted to change sheva mitzvos bnai Noach, then he would be a navi sheker and not a "genuine prophet". In any case we do not know of anyone who did this. The only two "prophets" that we know of who founded religions were weoll after prophecy in general ended at the start of the second temple era. Thus, the two modern invented religions could not have involved genuine prophecy.

When Did Prophecy End For The Non-Jews


Tomb Awakening time

Question: Why did the Necrons not awake at same time during The Great Awakening? Some awoke decades before others, and some Tombs never awoke to begin with. If Awakening was more synchronized they could have conquered the Galaxy with relative ease.
Comment: because even necron technology isn't perfect and is not impervious to the effects of time just like any other technology in 40k. I also doubt they would conquer the galaxy considering the amount or grimdark and endless was between anything and everything
Answer: Quoting from the official Warhammer 40k wiki

For 60 million Terran years the Necrons slept, voicelessly waiting for their chance to complete the Silent King's final order: to restore the Necron dynasties to their former glory. As the centuries passed, ever more Tomb Worlds fell prey to malfunction or ill-fortune. For many, the results were minor, such as a disruption to the operation of the Tomb World's chronostat or revivification chambers, causing the inhabitants to awaken later than intended -- but some of the Tomb Worlds suffered more calamitous events.
  Cascade failures of stasis-crypts destroyed millions, if not billions, of dormant Necrons. Some Tomb Worlds were destroyed by the retribution of marauding Eldar, their defence systems overmatched by these ancient enemies of the Necrons. Other Tomb Worlds fell victim to the uncaring evolution of the galaxy itself. Tectonically unstable planets crushed Necron strongholds slumbering at their hearts; stars went supernova, consuming orbiting Tomb Worlds in their death throes. And everywhere, inquisitive lifeforms scrabbled and fought over the bones of Necron territories, causing more damage in their unthinking search for knowledge than the vengeful Eldar ever could.

Basically what happened is time happened, a lot of things changed around them while they slept, and even their advanced technology (which in it's peak rivalled that of the Eldar and the Ancients) wasn't immune to the damages of time, their chambers and machinery fell to disrepair, went out of tune or destroyed all together. in 60 million years a lot could happen.
Comment: Sorry I had to downvote this because you say it's from the 'official' Warhammer 40,000 wiki. As it stands I don't think there is an official wiki and at the bottom of the wiki you link to it actually states
'This web site is completely unofficial and in no way endorsed by Games Workshop Limited or Fantasy Flight Games.'
I know it's a small point but it could potentially be misleading calling it 'official' as we all know GW change things as and when they want
Comment: Nice catch, but I think it's a good as it's gonna get, most of the lore is open for the player to fill in for his own game. There may not even be an 'official' reason, and if there is/was it's still liable to change as new codices get published and fluf gets retconned. WH is meant as a game setting first

Tomb Awakening time


How to get the Vista achievement?

Question: Is it a reference to Windows Vista? Is it an actual vista of an entire level from top? Where can I find this particular secret?
Answer: As usual in Serious Sam 3, the area in question is in serious plain sight. Acute players will have noticed this small green blinking item in The Power of The Underworld, roughly 400 kills into this serious level (after the serious infinite rocket storage).

It's seriously right under the crosshair. But how the hell would you get up there?
Climb on this seriously damaged wall further ahead, opposite the construction area leading to the next serious part of the map.

From there you'll see serious "secret keys" blinking in serious purple. Go back to the where that green item is located - the serious gates will now open for you.
You'll find a seriously long ladder on your left, before heading through the second gate. Climb it up, and, sure enough...

It's no crash to desktop, but it's a serious sight to behold, plus you get to have a peek on the following serious area. A very good peek I might add, since the green blinking item just around the corner is a serious sniper rifle. Unfortunately, it only comes with 5 serious shots and it appears it only can hold 10 anyway.
Remember to take the ladders on your way down, or you'll simply crash under your serious weight and suffer a seriously humiliating death. You can simply start taking the stairs with E, then jump off them and press E just before reaching the ground serious fast.
Comment: Spoiler alert: you really don't get a chance to use it :(
Comment: You can't be serious :(
Answer: It is in the Power to the Underworld level.
From this walkthrough:

In the final courtyard before exiting into the final open arena, on
  the middle left side, on the roof of the rooms there, there are some
  Secret Keys sitting against the wall. Simply climb up towards the
  final open arena, but instead walk along the edge of the wall until
  you find them. After getting the keys, go back to the pylon with the
  locked metal-gates, in the previous wide corridors. The gates will
  open revealing a ladder leading up to a secret Vista.

Here is a video that shows you where to go:

How to get the Vista achievement?


How do I test a 220v tanning bed without an outlet?

Question: I have been blessed with a tanning bed that runs on 220 plug, which I do not have in my home. Before I pay someone to put a 220 outlet into my home, I wanted to know if there is any way I can test the tanning bed first to see if it works first?
Comment: I'm voting to close this question as off-topic because it has nothing to do with home improvement.
Comment: Basically what @noybman said. Your question implies you are not comfortable installing a 220V outlet yourself. Therefore, your only option is to find an outlet that uses the same plug as your tanning bed and give it a try. If you post a picture of the plug we could tell you if you are likely to find such an outlet in your home but your best bet is to just compare it to the dryer or range plug. Most other 220V appliances in your home will be hardwired and I wouldn't advise you to take them apart.
Comment: *Now you know why you were "blessed" by it.*  220V tanning beds are like Christmas fruitcake that keeps getting regifted.  Do you have an electric dryer socket and your dryer is gas?  Or wiring for an electric water heater and it's gas now?  This job will be a lot cheaper if you put the tanning bed there.
Comment: If at all possible, ask the person you got it from if you have any faith they would tell you if it has issues. If you moved it to your home already, (or didn't), you could always plug it in elsewhere to test it if that's an option at all. Check behind the clothes dryer, in a basement or utility rooms, and also look behind the stove or in a garage (are there any double ganged breakers in your breaker box)? Do you have spare slots on your breaker panel? Anyways, I'm not certain anyone can tell you how to test it short of plugging it in and trying it. There are bulbs, controls, etc to test
Comment: @DanielGriscom, this seems like it would be a major appliance, so it would be on topic
Answer: One option, if you truly don't have any 220v outlets in your home, is to take it to a local RV park/campground.
Most campgrounds have multiple outlet types and are easily accessed by a truck so I think this could be a great way to test an electric appliance before moving it into your home. You'll need a site with a 50 amp hookup. I'd try public campgrounds before private ones.
Comment: I've never seen a tanning bed with a 50amp plug or for that matter a straight blade plug.  If it's a factory cord it will be twist lock.
Comment: This is a neat idea but not going to work for the reason @Tyson outlined. The locking plug is a safety feature and I don't think you will find a UL-listed adapter to defeat it (e.g. L6-30P female to L6-30R male). The adapters all go the other way around.
Comment: Yeah, I'm not familiar with what plugs are typical on tanning beds. I just know that the 4-pin 50 amp connector has the split phase voltage needed for 220V appliances. If the tanning bed uses a locking 3 pin connector, a cord like this might work: https://www.amazon.com/Conntek-1450SS2-15-Temporary-Generator-Straight-Blade/dp/B0046C6G7O
Answer: You can't fully test it without plugging it in.  If you have an electric stove or an electric dryer, you may be able to plug in to test it there.  Otherwise, the electrician may be able and willing to temporarily tie it in at the box so you can make sure it works.  You may find a generator with the same plug, too.
However you go about it, you need to have power to it to test it.


Why Italian monolingual dictionaries usually take complex/archaic examples from books instead of creating simple examples?

Question: Why Italian monolingual dictionaries usually take complex and/or archaic examples from books instead of creating simpler examples, like the monolingual dictionaries of other languages do (eg Cambridge English dict, RAE Spanish dict, Larousse French dict, Duden German dict) ? That makes them much harder to read and understand.
Comment: I'd disagree with your statement. Which dictionaries are you referring to? Would usage examples in dictionaries like Hoepli, Garzanti or Sabatini Colletti look archaic to you?
Comment: Treccani is usually referenced in this website and it seems to be the one of the most popular monolingual Italian dictionaries. I think it is a perfect example.
Comment: This question was partly prompted by another one where the [_Grande Dizionario della Lingua Italiana_](http://www.gdli.it) was cited, but keep in mind that it corresponds, if anything, to (the complete, huge) Oxford English Dictionary, which does not exactly eschew complex and archaic examples. One of the strengths of both OED and GDLI is exactly the possibility of reconstructing one word's history through its uses along the centuries.
Comment: Bordering on the OT: classic English dictionaries also tended to record every last word (including typos) by Shakespeare, Milton, Dryden etc.: https://www.etymonline.com/columns/post/the-impossibility-of-a-dictionary
Answer: While, as DaG has said, this tendency has been decreasing (and probably absent from more modern dictionaries, although I still remember it quite alive in the Devoto-Oli, the dictionary I used in school), it is true that Italian dictionaries traditionally prefer to give examples from literary sources. While I cannot conclusively provide a reason for this, I think that examining the history of dictionaries might shed some light.
The first dictionary of Italian (and almost the very first monolingual dictionary in any language), is the Vocabolario degli Accademici della Crusca. This dictionary was compiled explicitly with the intention of using it to define what the Italian language was. In fact those were years when the questione della lingua was raging. The Accademia was strongly influenced by the ideas of Lionardo Salviati, one of the great exponents of the purismo [1]. Essentially they argued that the language was perfected in the Florentine of the thirteenth and fourteenth century, and that anyone wanting to write "good" Italian should try to conform to that norm as much as possible. This was different from the "classicist" position of Pietro Bembo (who took literary quality, and not age, as the main criterion for inclusion of a text) and in strong opposition with the ideas of Vincenzo Colli and Gian Giorgio Tríssino, who argued for a norm more tied to the contemporary usage.
As a consequence in the first edition of the Vocabolario published in 1612 contained for every word at least a sentence of an author of the accepted period, to prove with certainty that the word respected the desired criteria. This turned out to be impossible, and a few posterior or not Tuscan authors were allowed on a case by case basis. However some great authors like Torquato Tasso were explicitly excluded, as insufficiently "Tuscan" in the Crusca's opinion.
The Vocabolario was a smashing success, as it was vastly superior in coverage and presentation to the word-lists of the time. However the strong Florentinism provoked numerous criticisms, and in the third edition (1692) several authors, among which Tasso, were reintroduced.
Long story short, however, even if the Florentinism was attenuated the Vocabolario's success managed to make mainstream the essentially purist criterion: a word was part of the Italian language if and only if it was used in the (approved subset of) Italian literature, and contemporary usage is no guide at all. I conjecture that the immense influence of the Vocabolario is responsible for the tendency you remarked, even in other dictionaries.

[1] This name is a bit of an anachronism, since it was attached to the position only in the nineteenth century. Still, it's what the books I read use.
Comment: Present-day Devoto-Oli is such just in its name (or brand); it's now actually Serianni-Trifone. :)
Comment: @DaG I did not know that. I was referring of course to the edition available when I was in school (late 90s-early 00s), which was still curated by Devoto and Oli :). Good to know they did a new edition!
Answer: This question is very interesting, but is partially based on questionable premises.
1) Not all, and perhaps a minority of dictionaries "usually take complex and/or archaic examples from books". Both in the past (Fanfani and Rigutini's Vocabolario italiano della lingua parlata, for instance) and today there are dictionaries that put contemporary, spoken Italian first.
Among those, there are of course works specifically addressing Italian (mostly schoolchildren) and foreign learners. But, most importantly, several major dictionaries have a strong focus on modern Italian. I'll mostly mention late Tullio De Mauro's work. The most accessible is his online dictionary; see for instance the entry fatto, which illustrates the word with usual sentences and phrases from everyday language, and news and politics language. De Mauro was a great linguist especially interested in the different levels of use of Italian words and phrases, who also edited the multi-volume Grande dizionario italiano della lingua dell'uso, which, since its very title, gives a priority to Italian as it is actually used. See also De Mauro's "vocabolario di base della lingua italiana", a list of most frequent Italian words, coded according to their use and register.
Also – as per Gio's comment – (recent editions of) Hoepli, Garzanti,  Sabatini-Coletti or Devoto-Oli have a focus on contemporary Italian (new Devoto-Oli's very subtitle is Il vocabolario dell'italiano contemporaneo).
2) On the other hand, one of the uses of dictionaries is to be able to read and study Italian literature, from before Dante to today, so they have to record those "complex and/or archaic examples" too. Especially the larger ones, such as the Grande Dizionario della Lingua Italiana, Treccani and partly Zanichelli ones would be lacking if they didn't record rare and historical uses too.
3) Finally – but I'm sure someone else will cover better this aspect – there are historical reasons while Italian culture used to be in general somewhat more inclined towards written transmission of culture, tradition, purism and great past authors than towards present-day use, but my impression is that this is something we are overcoming now.
Comment: I think there are literature readers in all languages, but this phenomenon of using literary examples in monolingual dictionaries seems stronger in Italian. IMHO it is not necessary to have literary examples in a dictionary to be able to understand literature. In Brazil, we read Portuguese/Brazilian literature with some help from the minimalist definitions/examples of a Portuguese dictionary and it works fine.
Comment: @AlanEvangelista Have you browsed the non-Treccani dictionaries I and Gio are mentioning, before judging them all from only one? As to your HO, we'll agree to disagree.
Comment: Yes, I have checked De Mauro's online dictionary and at first sight it seems simpler than Treccani, but still complete. I'll start using it as my first option of monolingual dictionary. Thanks for the link! I wish that more answers in this site pointed to it. I'm sure that any foreigner learning Italian has a hard time trying to read Treccani.


Is it possible to take control of Blender with a standalone Python instance?

Question: I intend to make a framework for BGE using wxPython, being able to manage blend file libs,  datablocks of the blends, alternative ways to make logic and ease the project management in general. I need to use Blender to edit the blend files contents (add logic bricks, edit datablocks, etc), so at first I thought to call blender in background mode through command line and execute Python scripts generated by the framework to make the changes to the blends. However, that would imply to open blender (in background) and save the blend file for each operation, even the simplest ones (like renaming), or queue the changes and add a annoying 'Apply' button. So, I wonder if it's possible to 'take control' of Blender's Python using the framework's Python, so the user can see the changes by the framework in real-time while being able to do changes that the framework won't do (like modeling, texturing, animation, etc).
Is that possible? Thanks.
Comment: The 'exec_from_stdin.py' example from https://blender.stackexchange.com/a/101772/29586 is very similar - allows you to effectively pipe the output from one command into Blender to be invoked as python commands. However, it won't work as-is on Windows - Linux (and possibly Mac) only.
Comment: Would it be possible to fire up your framework from inside Blender, so the Python running your framework is already the same one that's controlling Blender?
Answer: You'll have to build it yourself, but you can build Blender as a Python module. You can then do import bpy and use it as if you're inside Blender.
Comment: The wiki was archived, I've copied the page to the new wiki.


Generating vector tiles with Mapnik

Question: Is it possible to generate Vector Tiles using the 2.2.0 Mapnik release? If so, please give a sample configuration or point to an example.
Answer: You could find a good point to start here.
Answer: It's the other way around. Mapnik is software to render images from data. Vector tiles are data. You can use Mapnik to render images from Vector Tiles. You cannot use Mapnik to output Vector Tiles.
Comment: Vector tiles are data, but "rendered" nevertheless. Mapnik does support rendering data into vector tiles, but there doesn't seem to be any built-in flag to do this out of the box. The link posted by MickyInTheSky has C++ headers that may add this functionality to Mapnik 2.2.0 and 3.0.x.
Answer: No, Mapnik 2.2.0 will not generate vector tiles out of the box. To enable this functionality, it must be compiled with C++ headers available here.

Generating vector tiles with Mapnik


drush: list of update-locked modules

Question: We excluded some modules from drush update (--lock=module_name). Is there a way to get a list of locked modules? A drush command or a file with the list?
Answer: There is no way to do this via Drush; the easiest way to find the locked files is with the find command:
find . -name ".drush-lock-update"
Answer: If listing the locked Drupal modules is something you do often you can create a drush shell alias.
Add the following code to your drushrc.php file. Your personal one is normally located at ~/.drush/drushrc.php There are 6 locations that drush will look for drushrc.php, see the example.drushrc.php file for more information.
$options['shell-aliases']['locked-modules'] = '! find . -name ".drush-lock-update"| sed \'s#/[^/]*$##\' | sed \'s!.*/!!\' ';

You can then run,
drush locked-modules

to see a list of locked modules. The code above in addition to finding the .drush-lock-update files strips this filename off and then strips off all but the module name from the path.

drush: list of update-locked modules


How is cohomology theory used in quantum field theory?

Question: Quantum field theory uses a large amount of mathematics and I was wondering about some applications of cohomology theory in QFT, I understand it has applications in string theory but I was wondering about possible applications in more traditional QFT.
Comment: possible duplicate: [Characteristic classes appearing in the real world?](https://physics.stackexchange.com/q/400080/84967).
Comment: @AccidentalFourierTransform i wouldnt say it's a duplicate since cohomology is definitely more than just characteristic classes.
Comment: This post (v2) seems _too broad_ as cohomology theory is applied to almost any area of QFT.
Answer: In the BRST quantisation of quantum field theories, cohomology does show up. The conserved charge associated to BRST quantisation $Q_B$ implies that physical states must be BRST-invariant via $Q_B |\psi \rangle=0$. It's easy to prove that $Q_B$ is nilpotent: $Q_B^2=0$ such that one can add a null state to any physical state without changing its BRST invariance: $|\psi'\rangle = |\psi\rangle + Q_B |\chi\rangle$ where $|\chi\rangle$ is not physical, but $Q_B |\chi\rangle$ is clearly exact and closed.
The equivalence classes under this equivalence relation are precisely the physical states:
\begin{equation}
\mathcal{H}_{\text{BRST}} = \mathcal{H}_{\text{closed}}/\mathcal{H}_{\text{exact}}
\end{equation}
$Q_B$ actually raised the ghost number by 1 and forms a cochain complex.
This is also used in string theory, but I didn't make any reference to it.
I don't know a lot about this, hence I may be wrong.
Comment: Good references for the applications of BRST are the various papers by Barnich, Brandt and Henneaux, e.g. https://arxiv.org/abs/hep-th/0002245.
Comment: Here is another use of cohomology: https://arxiv.org/abs/1610.01941
Comment: One major remark might be that the cohomology of the BRST complex is quite different from more traditional notions of cohomology, such as the ones used for charge quantization etc, due to the fact that one also takes into account the space of fields (the covariant phase space) and not only the geometry of the underlying spacetime.
Answer: Also not an expert, but let me throw a couple things out there.  Nakahara's book "Geometry, Topology, and Physics" is excellent.  He has an entire chapter on de Rham cohomology, along with applications to harmonic forms.  My vague recollection in terms of the physics application of de Rham cohomology is to understand when closed forms are exact (all exact forms are closed), which--again, if memory serves--is equivalent to asking when one can express a force or a field in terms of a potential in a path-independent way; basically, if your manifold is topologically trivial, then you're able to write down the potential.  But if your space is topologically non-trivial, then you can get things like the Aharonov-Bohm effect.
Comment: Not that your answer is technically wrong, but it is not really an answer to the question. OP is asking for applications specifically in QFT
Comment: Possibly a fair point, but I bet trying to quantize a gauge theory on a topologically non-trivial space will be especially difficult for this reason
Answer: Cohomology can be found lurking behind many condensed matter systems. More specifically, cohomology is the mathematical origin behind the Integer (Anomalous or conventional) and Fractional Quantum Hall effects in topological matter, such as topological insulators or Weyl semimetals.
Such systems can be studied by either using Quantum Mechanics, where we use single-particle states to calculate the relevant topological invariants, mostly the (first) Chern number, or by using Quantum Field theory through which we can study more carefully the transport properties of the system of interest via quantities such as correlation functions.
In the field-theoretical picture, Chern-Simons theories are very common. They are prevalent in research on the Fractional QHE, but in the past years they have become more and more commonplace in the study of the Integer QHE too.
If you want to see how quickly the Chern-Simons action can lead to the quantisation of the Hall conductivity with almost none of the assumption one has to do when tackling the problem from a quantum mechanical perspective, you can check out the first pages of Tong's basic but very informative notes:
https://www.damtp.cam.ac.uk/user/tong/qhe/five.pdf
Note that even though Tong does not mention the word cohomology, the "winding numbers" that he defines are indeed closely related (and sometimes equal) to the Chern number.
Edit:
You can find more on this topic and how comohology plays a role in the following notes by kauffmann et al: https://arxiv.org/pdf/1501.02874.pdf