Wallet forensic

Question: Someone who scammed me used this wallet to receive the BTC 12fmomENb5SSxR54Bitua71CZrc4oVQtmB he hasn't moved them from there since July 31st I'm trying to figure it if that wallet belong to any exchange so I can contact them because I have all proof that this person in fact stole from me...
Answer: I analyzed a bit with forensic tools and found that with high likelihood either you or the scammer (or both) have an Huobi.com account.
If I understand you right then 03281a511f38992dff51dee176c66dfc5f873e92cd76228956ca5099a27214fd shows the scam transaction and the input addresses on the left side are yours and you initiated the transaction?
If yes then wait until the funds of 12fmomENb5SSxR54Bitua71CZrc4oVQtmB move (as of writing no move), then the flow can be analyzed until the scammer cashes out by sending the funds to a known exchange address.
If no (hacker initiated the transaction): Then address 14trBCQy7eGqGHKTouGC24vFJoFBoofBmn belongs as well likely to the scammer (you should know it if you look into your wallet), address 1BAyMWsePjFXjURd7EAPxs7YzFZAnTuw8e belongs likely to the same person and sent some funds to address 19LoQjvaNvTtKeADkZfqsbWCkWqoyjsTiK which is a known Huobi.com address. In this case it depends on your and spammers jurisdiction and Huobi support and a bit luck if you can identify the spammer with police's help or legal action.
Wish you success!
Update Nov 19,2020:
The coins were moved and the 12fmomENb5SSxR54Bitua71CZrc4oVQtmB had a co-spend with address 12qVmVXgFEtimhPDEMuUdg4AApdgW4gUS4 which deposited and withdrew very likely in other transactions at poloniex.com. The same person very likely received a lot of BTC from bittrex.com . The BTC address 12qVmVXgFEtimhPDEMuUdg4AApdgW4gUS4 sent funds to BTC address 1DfYET2tnEU54K9r5hWxxb8dWr4uko9eP9 which belongs to bitfinex.com. The BTC address 1JEd1Nb5LXYVFiR9s1ZtXFdxvTKAYYCHNg (belonging likely to the same person) sent funds to BTC address 1PsXn2nruFCS2WCVedVo76yPGgaS6UXUrA which belongs to yobit.net .
So if you didn't receive your funds back in the meantime I'd try to involve law enforcement because the loss was not a low amount. The exchanges know if the scammer cashed out (bank account or id available) or if he exchanged into another coin to follow up from there. If the scammer was smart you won't succeed but it's difficult not to leave any traces.
Good luck!
Answer: In general, there's no way to know if that address belongs to an exchange.
This is especially true when the funds have not been moved/spent.
Similar questions:

Tracking the wallet owner of stolen bitcoins
Wrongly Transferred!
How can I confirm to whom the bitcoin address I sent a payment too?

Wallet forensic


Blood pressure measurement

Question: When measuring your blood pressure in your arm, when you hear the sound to measure the systolic, is that sound NOT the heartbeat?
Comment: what do you define by "heart beat"? The *sound* of the heart beating or the *rate* of the heart beating?
Answer: The sound in question is called the Korotkoff sound:

If the pressure is dropped to a level equal to that of the patient's
  systolic blood pressure, the first Korotkoff sound will be heard. As
  the pressure in the cuff is the same as the pressure produced by the
  heart, some blood will be able to pass through the upper arm when the
  pressure in the artery rises during systole. This blood flows in
  spurts as the pressure in the artery rises above the pressure in the
  cuff and then drops back down beyond the cuffed region, resulting in
  turbulence that produces an audible sound.
Comment: I'm glad you found that info. I wasn't sure if the question was asking about the sound of the heart or some artificial sound cuffs make.
Comment: @mattkaeo blood pressure + measurement = Korotkoff sounds, this what the question is about...

Blood pressure measurement


How does phonemic variation in vowel quantity (but not quality) work in e.g. songs?

Question: How does phonemic variation in vowel quantity (but not quality) work in e.g. songs? For example, there is a variety of Yiddish that has both /a/ and /aː/. They must differ in quantity but do not seem to differ in quality. How would one distinguish them e.g. if they were in the same place in a particular melody, or in rapid speech?
Answer: Songs are special since melody and rhythm dictate the length of a note. A lot of contrasts that are made in speech are neutralised in songs.
The rules for singing German songs prescribe only "pure vowels" (a, e, i, o, u, ø, y),
the phonemes ɛ, ə, ɔ, ɪ, ʊ, œ, and ʏ are to be replaced with the closest pure vowel. Vowel length is also not marked in sung German. Note that these rules apply to composed songs (Kunstlied, choruses) but are relaxed in pop songs: Xavier Naidoo uses a very long ɪ: in the chorus of the song "Ich kenne nichts".
Comment: Yes, context must suffice. And songs can be difficult to understand from listening to them.—I don't know whether similar rules exist for English singing and when they are applied.
Comment: So words whose phonological difference would be neutralized by this process are just told apart by context in such cases? On a related note, I've never heard anyone neutralize the difference between e.g. "fit" and "feet" when singing despite the difference between them being the same as German long vs. short i.
Comment: I hadn't realized that there was a tradition of avoiding [ɛ, ə, ɔ, ɪ, ʊ, œ, ʏ] in German singing. Which vowel is ə replaced with: [e]? What about in words ending in -er, like Kinder: would that be /ˈkinder/ according to the tradition that you are talking about?
Comment: @sumelic Yes, the schwa is replaced with an [e], even in the ending *-er*.
Comment: Is this the Bühnendeutsch standard? I'm pretty sure in most classical singing diction of German, the quality of lax vowels is carefully preserved and much attention is given to distinguishing the sung pronunciation of schwa.
Answer: I'm not actually sure what you are asking about – "phonemic variation in vowel quantity (but not quality) work in e.g. songs". Indeed, "long" vs "short" vowels in Germanic are typically associated with quality differences. But in many languages (Bantu languages, Japanese, Finnic and Saamic languages) length isn't indirectly expressed by quality differences. The phonetic difference between long and short vowels in those languages is one of duration (I take it that by "phonemic variation" you are referring to the fact that length is phonemically contrastive): long vowels are longer than corresponding short vowels by some amount (we do not have a particularly rich database of phonetic studies that established the ratio of long to short, but languages do differ in how much longer a long vowel is).
It's not clear what you mean by "e.g. song" – other domains for looking at vowel length include metrical structure, tone assignment, syllable structure... Ross & Lehiste The Temporal Structure of Estonian Runic Songs investigate the question for Estonian which has contrastive vowel and consonant length. Regrettably, I don't have a copy of the book, but my understanding is that the requirements of metrical structure for the runo match the foot structure of the spoken language, so for example a long vowel will not be in a metrically weak position (non-initial within the foot).


Artificial satellite in a Binary Star System

Question: Is it possible for an artificial satellite (in this case, an unmanned communications platform) to maintain a stable orbit directly around the barycenter of a Binary Star system, as in well inside the orbital paths of the two stars themselves?
Comment: Quick clarification - how long for and how much/little mass do you want to expend "station keeping"? With a sufficiently handwavy "unlimited" drive you could easily have an artificial satellite that stays on a less stable orbit for longer than one that has no drives that's on a more stable orbit. See here:https://en.wikipedia.org/wiki/Orbital_station-keeping
Comment: Well I was admittedly looking for an orbit that could remain stable on it's own, but I'm looking to use a large fleet of communication satellites all stationed around the barycenters of various binary systems. Given that each binary system would have its own properties, likely wildly different from one another, I could see station keeping being implemented for some of the more extreme cases. Thanks for the suggestion.
Answer: The barycenter is the common point around which both stars appear to orbit.
But it is only an artefact of their gravitational relationship, not a real thing.  Any object located at the barycenter would not be affected in any special way, and there is certainly no mechanism by which it could naturally orbit about that point.
If both stars have equal masses, then the gravitational forces from each star are equal, and so in theory an object could remain stationary at that point.  In practice though, it would need to be continually adjusting its position as the balance point is unstable, and even the slightest perturbation in the system would produce positive feedback and subject it to an ever increasing gravitational attraction toward one star.
If the stars have different masses, the barycenter is even more meaningless for the proposed situation.  Consider our solar system, with everything but the Sun and Jupiter removed from it.  The barycenter would be much closer to the Sun than to Jupiter (in fact only about 50,000 km from its surface) and so the gravitational force of the sun would far outweigh that of Jupiter.  Any object placed there would immediately fall into the Sun.  That the starting point happened to be the barycenter would be irrelevant.
Answer: I would take a look at Lagrangian points. Areas of relative stability between 2 large bodies and a smaller 3rd one. There is a point (not the barycenter) where the gravity forces generally cancel out known as the L1 point. The L1 point is between the 2 suns, and is going to be somewhat closer to the smaller of the 2 suns. If they are relatively the same size, the L1 point will be very close to the barycenter, if the mass difference is large, the L1 point will be rather close to the smaller star. For example, the earth/sun L1 point is .01 AU (or 1/100th of the average distance between the sun and earth) away from the earth.
The L1 point is technically unstable, but even current tech considers station-keeping necessary to be fairly minor. There are several other locations that will give you a general "stable orbit" known as the L4 and L5 points, but they tend to be roughly the same orbit as the larger stars.
Comment: The wiki I linked has the math... but it is quite beyond me sadly. A rough aproximation can be found by finding the point where the gravity strength is the same. Gravity goes up directly according to mass (so a star twice as heavy will have twice as much gravity) and goes down based on distance squared. (so if you get twice as far the gravity is only 1/4 as strong)

if Star A is 4 times the mass of star B, the L1 point is going to be twice as far from Star A as Star B. If they are the same size the L1 point would be in the middle.

Non-circular orbits are super super messy.
Comment: I hadn't considered the Lagrangian Points, but they just might work. How would one calculate the distance of the L1 point between the two suns?


What are the effects of upgrading the Mayor's Mansion?

Question: I have plopped the Mayor's Mansion, and for every 4 or 5 hours of in-game time that I maintain an approval rating of 75% or higher, I am prompted to upgrade it. Since it is free to do so, I oblige. However, what is the benefit of this? Does it increase land value even further each time I click? All that seems to be happening is a firework show.
Answer: I did some more in-depth observations last night, and here is what I found:

Each time the Mayor's Mansion is available for an upgrade, that means you have crossed an approval rating thresh-hold, and your sims wish to give you a gift.
The gifts take the form of add-ons to your mansion, each which costs a little extra upkeep each hour to plop (about $10), but slightly increases the land value around the mansion even further.
Each add-on is slightly more difficult to obtain than the last, meaning you'll need to hold a certain approval rating for longer, or simply achieve an even higher approval rating.
Gifts include the following structures: Flag of the City, Mayor's BBQ Pit Patio, Circular Fountain, Mayor's Statue, Balcony, Guest House, Guard Post, Street Car Garage, Extension Wing, Limo Garage, Greenhouse, Tennis Court, Swimming Pool, Lookout Tower, Party Wing, Simcopter One.
Answer: According to the IGN guide, it "dramatically increases nearby land value."
Comment: I should clarify, beyond what the tool tip states about increasing land value, what does upgrading it do? Increase land value further?
Comment: @Tater596 - Yes exactly.
Answer: It is the single most dense land value effector in the game. It is the only building I have seen that will turn the value of the land around it dark turquoise.  Once it has most of the upgrades...


Could using an orifice for the wrong gas type damage a water heater?

Question: Question...Over the past 18 months, after our home was built, we learned our two tankless water heaters have been running propane through a natural gas orifice.    We discovered the issue after hearing a loud noise coming from one of the water heaters.   Could this have damaged the water heaters?   Thanks in advance
Comment: Is there no conversion adapter installed? If I recall correctly it's just a flow-rate difference and the appliance has to be rated for both fuel types.
Answer: Nat gas orifice is significantly larger than propane orifice , so the heaters have been exposed to more heat /flame than design ; that could be a problem. I learned this the hard way;  hooked up a nat gas grill to a propane bottle. On the lowest burner setting flame came out around the space between the top and bottom of the grill. In round numbers the gas molecules take up the same volume ( Ideal gas law) . In the nat gas molecule you have one C and 4 H to burn , in a propane molecule you have three C and eight H to burn. So the nat gas orifice is larger to let more molecules through , it lets the same larger number of propane molecules through producing more heat/flame.
Answer: From memory the propane orifice would be larger so by using the natural gas your heater would not get as hot as it would with the correct orifice so I do not think it would hurt anything.
Added :
Orifice size for natural gas range from # 54-31 (drill bit sizes)
Propane orifices range #62-48  so I had it backwards
The larger the number the smaller the hole. In this case there was two much going to the heater so it may have shortened the systems life , however since the air mixture was probably off it may not have been burning efficiently and wasting gas.
Comment: Ed, I think it's the other way around, he said they had propane going TO an appliance designed for natural gas.
Comment: The natural gas orifice I thought was smaller than the propane, maybe I remember it wrong , but I have converted stoves , bbq's and furnaces that only required an orifice change, some also required the jets in the burner to be changed also.
Answer: Damaged? Probably not, just inefficient and more prone to the flame blowing out.
Answer: An appliance designed for natural gas has the burner orifices (flame holes) designed for the pressure and flame temperature of a natural gas system. Propane burns with twice the energy of natural gas, so if you put propane through a burner designed for the lower pressure / lower yield gas, it will burn significantly hotter and potentially more dangerously. It will also likely waste a lot of heat because the heat exchanger in the water heater was designed for a specific amount of flame contact. So the hotter / larger flame coming from the propane will just go up the flue as waste heat. It MIGHT possibly cause damage to the heat exchanger, only the water heater mfr could tell you for sure, but it's a sure thing they will not tell you that it is OK.
Of concern here is not only this, but if someone did that with your hot water heater, could they have plumbed the propane into your entire house? If so, there is significant risk of that excess heat causing damage to the fire box of your heater, which can then lead to gasses like carbon monoxide getting into your living space and poisoning you! There have been news reports of whole families being killed as a result of substituting propane for natural gas to heat their homes (without making the necessary changes).


Housing Price Index - How to determine if Housing Marketing is high or low

Question: What is the best source/website for seeing if the housing prices are high or low? I am looking to buy a home but don't know where to look confirm if the housing prices in aggregate or by city/state are high or low.
Comment: What country are you in?  In the US, I'd generally use the Case-Shiller index https://fred.stlouisfed.org/categories/32261 for whatever geographic region you're interested in.  Other countries would use other indexes.  Taking a step back, though, I'm not sure what action you'd take based on the index.  You have to live somewhere after all so the choice is between renting and buying.  That's not something that a housing price index is going to help you with.
Answer: You can always look at historical averages in a market to see where prices are now comparative to the past, and a large short-term rise in prices might be potentially a sign of a local real estate bubble.
One of the interesting phenomena we witnessed here in Colorado in the 1990s and even the early 2000s was a large influx of people from California who were drawn by a growing tech industry along the Front Range of the state.  After selling their own homes in California, they found they could afford a much larger home here for less than what they sold their last homes for, and when sellers realized they could GET more, prices began to rapidly rise.  That trend has never really slowed too much (outside of the post-2008 national slide in prices), and Colorado (Denver and Colorado Springs, at least!) remains one of the most expensive real estate markets in the country.
The point is that whether a market is high or low is often more a matter of affordability than anything.  What you consider to be expensive when looking at California prices is accepted as the norm there, and the opposite is true for people in California when they look around at the rest of the country by comparison.
Sometimes a good way to gauge whether a market is nearing its peak is to analyze the trend in how long properties remain on the market and whether they are selling at, above, or below asking price.  There will always be outliers in the data (a highly desirable neighborhood may always fetch asking price or more while a less affluent one frequently may tend to sell slightly under asking price, even in good times), but if the general overall trend is moving toward longer times on the market and properties having their prices reduced before selling then it might be a pretty reliable indicator that the market is flattening out, in which case you should exercise some caution before jumping into buying a home.


How to create a Stress Curve

Question: How would I create a stress curve using this given data: Time(s),Extension(mm),Load(N,Tensile strain (Extension)(mm/mm),Tensile extension(mm)
Comment: What kind of stress curve?  I assume you mean stress-strain; but you could graph a few things here.  It's basically just plotting numbers in a graph though, there isn't much engineering required here.
Answer: to calculate the stress, you divide load by the surface area of your section be it a wire or rod or square bar.
Remember $$\sigma = \frac{F}{Area}  $$
But if you want to graph a stress/strain curve, you divide all the strains to initial length of your sample. you get numbers starting at 1 and increasing to say 1.0, 1.03 corresponding to increasing loads. You drop the 1 and plot the decimal parts on x axis and stresses on the y axis.
Edit
Explaining why i did not consider the change in surface area of the wire or bar.
Usually we ignored narrowing of the specimen before we reached plastic region in our lab. And bottle necking happens just before the rapture. You can estimate 30% of tensile strain but it doesn't add up to a significant amount. Say you have 6% tensile strain , you get 0.018 radial shrinking which raised to the power of two is 0.0036 which is smaller than tolerance of many of the jacks you use to test the tensile strain.
Comment: But there are different definitions for stress. For example the area can be taken as constant, namely the area before any force is applied, or the true area which will shrink as the sample stretches.
Comment: @fibonatic true but usually you dont know the new area

How to create a Stress Curve


Software to automatically sync my Facebook events to Google Calendar

Question: I'm using Google Calendar for my time planning. I need to see all Facebook events I declared I'll attend, I'm interested in, or was invited. Manually copying events is tedious and prone to errors. Is there a software I could use to automatically update my google calendar, instantaneously or for example once a day, with events from Facebook?
Answer: You don't need any tool in theory:

Go to Facebook -> Events -> Your events.
Right click Add to calendar button on top right.
Copy URL.
Go to Google Calendar -> Add calendar -> From URL.
Paste the copied URL.

And that's it. External application may be nice for further filtering, but your choice if you trust it with your data.
Answer: A friend recommended to me this online tool:
https://eventcal.flown.io/
So far, it seems to work correctly. It takes some time for it to sync up, but generally it synced all my events after one night of waiting.
I have no association with the tool or the author, and I don't think that friend who recommended it has any.


If I copy from any source do I also have to use inverted commas along with the source?

Question: I am writing a report in which I have to define some terminology. If I copy from any source and paste it and mention the source will it be enough or do I also have to mark inverted commas along with the source.
Comment: This question strikes me as a better fit for English Language Learners. The mechanics of quotation in English is not specific to academia. On the other hand, there are no moderators to do a migration...
Answer: I'm assuming you mean "quote marks" as I've just used them. Yes, you need to indicate precisely what you have quoted (copied). The usual method is quote marks, but some other options are available if you make your intent clear. For example you can indent paragraphs like the following, indicating that it is a direct quote.

When in the course of human events...
Answer: Yes, if you directly copy text parts, you need to use quotation marks (the inverted commas) and cite the source.
However, in most cases it is better practise to not use a direct copy of the text with quotation marks, but do an indirect copy, i.e., you paraphrase the source material with your own words. Then you do not use qutation marks, you just cite the source.
The reasons are that you can write a text that is better to read with the indirect copy method, and that you show that you have understood the source material by citing it with your own words.
Comment: Usually I'd agree that paraphrasing is better than direct quotation, especially if this is summatively assessed undergrad work in which OP is expected to demonstrate that they've understood (not just memorised) some information.  However, OP mentions defining terminology, and in a definition, it may be beneficial to stick to exactly the standard wording.


Failed when parsing body as json - call Rasa API with request.post()

Question: I'm writing a function to call Rasa API for intent prediction. Here is my code:
def run_test():
    url = "http://localhost:5005/model/parse"
    obj = {"text": "What is your name?"}
    response = requests.post(url, data=obj)
    print(response.json())

I also start Rasa server with this command: rasa run -m models --enable-api --cors "*" --debug
And here is what I got from Rasa server terminal:

In the terminal that I excuted run_test(), I got this result:
{'version': '2.7.1', 'status': 'failure', 'message': 'An unexpected error occurred. Error: Failed when parsing body as json', 'reason': 'ParsingError', 'details': {}, 'help': None, 'code'
: 500}

Anybody help me to solve this problem? Thank you very much!
Answer: I found the solution:
Only need to use json.dumps() the object, because object in Python is different than object in json.
def run_test():
    url = "http://localhost:5005/model/parse"
    obj = {"text": "What is your name?"}
    response = requests.post(url, data=json.dumps(obj))
    print(response.json())


Is the Young's modulus the same for compressive and tensile test?

Question: I want to know the Young's modulus for a compressive test, but I have just a tensile test. Are they of the same value?
Answer: For a linear isotropic Hookean material, the Young's modulus of elasticity is the same for compression and tension.
$E = \frac{\sigma}{\epsilon}$
where $E$ is the Young's modulus, $\sigma$ is the normal stress and $\epsilon$ is the normal strain.
Answer: The equivalence is derived here, for example. Briefly, any smooth energy minimum examined up close looks like a parabola, which is symmetric around the equilibrium point. A parabolic strain energy corresponds to a linear restoring force (corresponding to Hooke's Law) and a constant stiffness in both tension and compression.


What denominations subscribe to or accommodate the Annihiliationist doctrine of hell?

Question: I am interested in what denominations allow or require the belief that hell is the annihilation of a conditionally immortal soul rather than the eternal suffering or eventual redemption of such.
Comment: The correct term for this is Annihilationism, not Conditionalism. The latter term means something else entirely, see [this answer on your other question](http://christianity.stackexchange.com/a/25820) for an explanation of when to use which term.
Answer: From the wikipedia article on Annihilationism (4th paragraph):

Some Christian denominations which are annihilationist were influenced by the Millerite/Adventist movement of the mid-19th century. These include the Seventh-day Adventists, Bible Students, Christadelphians and the various Advent Christian churches. Additionally, the Church of England's Doctrine Commission reported in 1995 that "[h]ell is not eternal torment", but "non-being". Some Protestant and Anglican writers have also proposed annihilationist doctrines. (emphasis mine)

Later in the article it cites Jehovah's Witnesses (see this question) and the followers of Herbert Armstrong as other examples


What are the plants in Trigun?

Question: I know that they generate energy and they're used like power plants but there's also a person or creature of some sort inside. What are the plants exactly and how is it that Vash can communicate with them?
Answer: In the Trigun Universe, Plants are constructions, built by humans, to hold and house powerful beings that can create energy, food, and even water. Not much else is revealed about the beings themselves in either the manga or anime that gives away where they came from, how humans learned to harness their power, or what they truly are.
As for why Vash can communicate with them:

 Both Vash and Knives are "products" of the plant. It is unknown if they were born by the plant on the ship, or how they came to be, as it is said that they were found near the plant itself. Vash and Knives both show many characteristics like the plant, and also many dissimilarities. For example, both show increased control over their powers, including being able to generate guns at will, and both have a far longer life-span than humans, while aging to the mid-30's look faster. They are also able to communicate with the plants, as Vash demonstrates on a few occasions. However, unlike plants, they do not need to be contained in a special environment to survive, and they are male, where as every plant form that can be seen is female.
Answer: This is in Wikipedia in Spanish and I just translated it for the question:

In the future, Earth has been overpopulated and natural resources and environment are in a state to disappear soon. In this situation they create the project "Seeds", in which, to ensure the survival of the species they sent into space a fleet of spacecrafts in which a great number of people are contained in suspended animation.
These ships used as feed system a technology called "Plants", a power generator housed in an entity whose core is almost pure energy and serves as a source of power to the ship.
In one of these ships, a small crew is responsible for guiding and find a planet that can accommodate the human race. One day, an anomaly leads to the reactor to discover there that not only the Plant has given birth two newborns, but unlike the rest of their species, they look more human and can survive outside the reactor.
Answer: From what I can tell, the plants were not created by humans, they were harnessed by humans as an energy source. The humans in this series do not seem to have a complete understanding of the plant entities. Vash can communicate with other plants, since he is a plant (or as the anime suggests a possible plant-human hybrid). Note that a crew member dies in the ship's engines just prior to the appearance of Vash and Knives.

What are the plants in Trigun?


Civi Event RSVPs

Question: Is it possible to show how many spots are available for RSVPs/registration for events as people are registering on the website (in real time)? For example, say someone wants to register for "X" event, they go to our calendar event on the website, see we have 2 spaces left available but they want to purchase 4 tickets. As of now, they have no way of knowing until they enter how many tickets they would like to purchase.
Comment: what cms? for drupal you may be able to get a view block showing on the info and/or registration page showing how many places remain
Comment: It is drupal. So you think a view could be created to show registration totals? Good idea. I can give it a try.
Answer: For sites using Drupal you should be able to get a view block showing on the info and/or registration page showing how many places remain - may require a bit of php in the view to do the subtraction of total places minus registered participants

Civi Event RSVPs


What's the best way to learn the French?

Question: Recently, I have been very attracted to the French defense, as I feel as though it is perfect for my style. However, I am aware that the French is highly theoretical, which is why I need a good, detailed, and organized way to study the theory and move orders of all the variations. Any suggestions?
Comment: There's a few sharp lines in the French but overall it's probably one of the least theoretical responses to 1.e4.
Answer: The fact is that you will need to pick a good book, which is difficult since there are a million books out there on the French.
When starting out with a new opening, picking a book that is heavy on theory is not so important as is a book that presents ideas well. For this purpose, I suggest the book "Mastering the French" by GM Neil McDonald.
I also suggest the book "Winning With the French" by GM Wolfgang Uhlmann. He was probably THE authority on the French during his peak years, and never played anything but the French in response to 1.e4 during his career (or so they say). The book is exclusively taken from 60 of his games, and the explanations are very good, but watching how a master of this opening handles it will be invaluable.
From there, you need to just start taking in one chapter at a time, but not necessarily in order. You want to take the most common lines first since you are more likely to encounter them early on. Spend at least a week on each chapter, and play some blitz games with a friend, who is willing to give you practice in each variation.
You will pick up the main ideas pretty quickly this way.


How are numbers greater than 255 denoted in binary?

Question: The binary value for 255 is 11111111, with all of the memory locations used up.
How can greater numbers, for example, 481 be denoted?
Will they be written singularly, like (considering the above example), 00110100 00111000 00110001?
Comment: Your title doesn't match your question well..  binary exists independently of computers and is not in itself, limited by memory locations of 8 bits.  You're really asking how are numbers > 255  stored on computers. Also your question is not easy to read.. as somebody would have to take out a calculator to see what you are asking/getting at when you give that long binary string. That is totally unnecessary.
Comment: If they exceed 255, 2 bytes are used instead of 1. Just like using 2 digits when writing 10 instead of 9.
Answer: You just keep going... 2^8, 2^9, etc. split into 8 bit words. 481 would be 00000001 11100001 in binary... or 2 bytes worth of information. You have 256+128+64+32+1 in your example.
Answer: It depends on the number of bits you use. In your example, you've used an 8 bit (one byte) number, which does max out at 255.
Ever since forever, computers have used numbers that are larger than one byte.
For example, in Fortran (invented in 1977) 'real' numbers use 4 bytes, and can store numbers up to
11111111 11111111 11111111 11111111 = 2,147,483,647
For when that isn't enough, Fortran includes the 'double precision' numbers which use 8 bytes.
Comment: I learned Fortran IV back in 1967, so your 1977 date is wrong.  'Real' numbers are floating point, but the example you cite is an integer.  Also there have been  computers that were limited to just single-byte values (for demo or proof-of-concept purposes)  (i.e. silicon wasn't always as low-cost as it is today).
Comment: Agreed. I was simplifying things a little given the question. I'll admit I wasn't around to remember Fortran in the 60s and keep seeing references to '77 as 'the old version'.


Origin of "rank hath its privileges"

Question: It's often seen with "has," but the frequent appearance of "hath" suggests the saying may be much, much older. Early Modern English always suggests Shakespeare to me, but my Google-fu hath failed me in this instance. Perhaps someone here can shed some light.
Comment: uh... Darmok and Jalad at Tanagra?
Comment: The *hath* could easily be archaic grammar added for artistic purposes. Trust in the Google-fu.
Comment: When General Grok gave some orders to the Cave Battalion.
Answer: The oldest instance that I could find in a series of Google Books searches for the expression is from Harriet Lee, The Mysterious Marriage; Or, The Heirship of Roselva: A Play (1798):

Lord Albert. (striking him.) Lying fool, begone!
Rodolphus. Nay, no liar, I swear—nor so much of a fool as not to know that if rank has its privileges, age and fidelity are not without theirs. I humbly wish your Lordship a good night. And when you have a follower more faithful than myself, may heaven and you reward him as he serves!

But it also appears in A Lady, Life and Death of a Monkey; or the Village of Alton: A Tale for Young Persons (1814):

Some persons affect to rail at rank and title. Let such consider, if they can, the beauty, the harmony, the convenience, the happiness, that result from the different ranks in society—and the dependence which each has on the other. In this happy island each rank has its privileges, and all ranks are free.

Almost as old as the first of these instances is an instance arguing (more directly than Rodolphus did) that age has its privileges. From Thomas Gisborne, An Enquiry Into the Duties of the Female Sex (1806):

The spring and summer of life are past; autumn is far advanced; the frown of winter is already felt. Age has its privileges and its honours. It claims exemption from the more arduous offices of society, to which its strength is no longer equal; and immunity from some at least of the exertions, the fruit of which it cannot enjoy. Deprived of many active pleasures, it claims an equivalent of ease and repose.

And, of course, youth put in an early claim as well. From "Revolt at Princeton College," in The Weekly Inspector (May 9, 1807):

"For your individual self, sir, as you feel within a spirit of freedom and independence, capable to revolt from tyranny and resist oppression, we expect you tio adhere to your deliberate resolve, to evince to the world that you are capable of acting for yourself, and that AGE should not sanction IMPERTINENCE, that youth has its privileges, and that the GENIUS of REVOLT shall come forward to support them, whenever the hand of presuming authority shall attempt to level or abridge them."

In approximately the same time period, Edmund Burke, while not acknowledging its claim to privileges, concedes that wealth has its "natural weight." From Burke, "Thoughts on French Affairs" (1791), in The Works of the Right Honourable Edmund Burke, Collected in Three Volumes (1802):

As to the monied men—whilst the Monarchy continued, there is no doubt, that merely as such, they did not enjoy the privileges of nobility, but nobility was of so easy an acquisition, that it was the fault or neglect of all of that description, who did not obtain its privileges, for their lives at least, in virtue of office. ...
What institutions and manners together had done in France, Manners alone do here. It is the natural operation of things where there exists a Crown, a Court, splendid Orders of Knighthood, and an Hereditary Nobility; where there exists a fixed, permanent, landed Gentry, continued in greatness and opulence by the law of primogeniture, and by a protection given to family settlements;—where there exists a standing Army and Navy;—where there exists a Church Establishment, which bestows on learning and parts an interest combined with that of Religion and the State; in a country where such things exist, wealth, new in it's acquisition, and precarious in it's duration, can never rank first, or even near the first ; though wealth has it's natural weight, further, than as it is balanced and even preponderated amongst us as amongst other nations, by artificial institutions and opinions growing out of them.

One possible source of these attributions of privileges to various special class is a 1696 translation of La Bruyère's Characters. From Jean de La Bruyère, Supplement to the Characters, or Manners of the Present Age, sixth edition (1696/1713):

O Times! O Manners! cries HERACLITUS; O miserable Age, fill'd with bad Examples! O wretched, wretched World, where Virtue is persecuted, wjere Wickedness domineers, where it triumphs! ... Who can, with dry Eyes and an undisturb'dd Soul, behold such lamentable Things? There is no Office, no Post but has its Privileges; there is no Incumbent, no Occupant, but is at liberty to talk, plead, sollicite to defend his Rights: The Royal Dignity alone enjoys no longer its Privileges; Kings themselves have renounc'd them.

Conclusions
The earliest exact match I could find in Google Books search results for "rank has its privileges is from a 1798 play by Harriet Lee. However, quite similar assertions were made at approximately the same time about age, youth, and wealth, too.
La Bruyère may have influenced the expression with his observation in 1696 that there is no office and no post but has its privileges—however, it is difficult to assert this connection with any degree of certainty.
Answer: Looking through Google Books results, I haven't found anything so far that indicates that "rank has/hath its privileges" is a sentence of very great antiquity.
There is a similar sentence in Hood's Magazine, Vol. IX (January to June, 1848):

"Property," it is said, "has its duties as well as its rights;" to this may be added, "Rank has its duties as well as its privileges."

(p. 7; "The Times; or, Modern Philosophy")

It seems likely to me that the "snowclone" "X has/hath its privileges" is older than the specific saying "Rank has/hath its privileges". I'm not sure, though.
Here's an example of "hath its privileges" from 1827:

grief, like impatience, hath its privileges

(Tales of the Crusaders, Tale II. "The Talisman." Tales and Romances of the Author of Waverley, Volume VI, p. 233.)

Origin of "rank hath its privileges"


Identifying Confounders

Question: Currently I am interpreting NHANES data through proc logistic in an attempt to identify confounders; relationship of interest is 'rate of depression' from 'total savings.' However, when I employ multi-categorical variables like race and or marital status, I cannot employ the 10% rule as encouraged by my professor to identify confounding. Many of the subcategories are split on whether they are or are not statistically significant at the alpha 0.05 level under the table of Analysis of Maximum Likelihood Estimates. That said, I was encouraged to employ a type III Analysis under proc logistic which identifies if the overall relationship is statistically significant rather than looking at individual p-values (correct me if i'm wrong please). That said, I was wondering if someone could help me understand how 'Race' under the Analysis of Maximum Likelihood Estimates is only partially statistically significant but its p-value under the type III test for the variable of interest is well below the alpha 0.05 level (makes no sense). I will include a picture of the output down below in an image. Thanks
Answer: First, there is no way to identify confounders from a multivariable logistic regression. Confounding is a causal concept that requires an understanding of the causal system. The presence or lack of an association in a regression does not inclicate the presence or absence of confounding by the corresponding variable. It should not be used as a criterion to decide whether to adjust for that variable in a future model.
Second, understand that the coefficients for the race categories correspond to the estimated difference in the log odds of the outcome between each category and the reference category (in this case, Mexican American). It may be that these differences are fairly small, but it is possible that differences among the non-reference categories are large. Indeed, we see that the difference between Other Race and Non-Hispanic Asian is quite large: $.5111 - (-.5629) = 1.074$. This difference is twice as large as any of the differences between the reference category and the other race categories. The p-value on Race in the ANOVA reflects that there is a substantial effect of race; it just happens not to be between the reference category and the other race categories.

Identifying Confounders


tunnel into an SSH (not through ssh)

Question: Where I am located, I don't have access into a specific ssh host (through GIT) and I want to know if its possible to tunnel into it through something like proxy (even though proxy doesn't work with ssh). Can I SSH into one host and connect into another through the previous one's tunnel? Or something similar?
Comment: Hope this answer helps [http://superuser.com/a/727510/242890](http://superuser.com/a/727510/242890)
Answer: If I understand the question correctly, you need something like the following
ssh -L 2222:host1:22 -L 2223:host2:22 -L 2224:host3:22 user@middlehost

This is a command that you run on your local machine.  middlehost is the host you are able to log into from your local machine with ssh user@middlehost.  host1, host2, host2, are machines that you would like to log into but cannot from your local machine, but you can from middlehost.
After you have run the above command you need to run the following on your localhost to, for example, log in to host2
ssh -p 2223 user2@localhost

port 2223 is automatically forwarded to middlehost, where the original command forwards it to port 22 of host2.  From the PoV of host2 it is middlehost that is ssh-ing to it.

tunnel into an SSH (not through ssh)


Is there a clean way to retrieve the AWT event dispatch thread

Question: I'm trying to do some monitoring of the AWT Event Dispatch Thread's (EDT) health from a separate thread.  If I start missing heartbeats I want to dump the EDT stack trace.  The problem is the EventQueue doesn't expose a way to retrieve the current dispatch thread, the method that does is package private (probably for good reason). So I can either search through all the threads and look for a thread with a name like AWT-EventQueue-X or use an invokeLater or invokeAndWait and have my runnable save off the thread, something like:
EventQueue.invokeLater(new Runnable() {
    public void run() {
        eventDispatchThread = Thread.currentThread();
    }
});

Then every time I go to dump the thread stack I have to first make sure the EDT I've got is still alive and if not go through the whole process again to get the thread.  I'm just looking for a cleaner way to do this.
Answer: Alternatively, you can extend EventQueue, as shown here.


Jquery: What is the difference between stop(true) and clearQueue()

Question: What is the difference between using a stop() with the clearQueue parameter set to true and just using the clearqueue(), and if there is no difference why both?
Answer: From the api docs, .stop() is meant only for animation, however .clearqueue() will remove any function attached to a standard jquery queue.
From the docs:

When the .clearQueue() method is
  called, all functions on the queue
  that have not been executed are
  removed from the queue. When used
  without an argument, .clearQueue()
  removes the remaining functions from
  fx, the standard effects queue. In
  this way it is similar to .stop(true).
  However, while the .stop() method is
  meant to be used only with animations,
  .clearQueue() can also be used to
  remove any function that has been
  added to a generic jQuery queue with
  the .queue() method.
Answer: jQuery supports a number of queues, the most common of which is the fx queue for animations. .stop() works only on the fx queue, while clearQueue lets you specify some other (custom) queue.

Here is an example with a custom queue:
// First function to queue
function a1(next) {
    setTimeout(function () {
        alert("one");
        next();
    }, 1000);
}

// Second function to queue
function a2(next) {
    setTimeout(function () {
        alert("two");
        next();
    }, 1000);
}

// Queue both functions and start it off
$('body').queue('alerts', a1).queue('alerts', a2).dequeue('alerts');

// Clear the queue to prevent the second alert from showing
$('body').clearQueue('alerts');

See the demo.


style/class file for LACUS

Question: Are there any linguists here who know of a style/class file for the LACUS conference? My tex-fu isn't quite good enough to make my own. The guidelines for it are here, but lacus.org doesn't seem to have any template that can be used, except a Word template for abstracts. What makes things worse, googling for "latex lacus" brings up all of these documents with "Nam lacus libero" and other Latin phrases.
Answer: I think the best would be to email LACUS institution (there are several emails, for example a publication director) and ask there for an template. If they have no template ask them wether they can work with a tex file or not.
If they do not offer a LaTeX template you have to do it by your own, following the design guide.
Comment: Ah man, not only do they not have a template, but they require Word documents for submission :(
Comment: It sounded like it was because they just didn't know how to use it, or the people who were formatting the entire thing could only edit word documents.

style/class file for LACUS


Can I use a 3.5mm mic in an ipod touch?

Question: I have a microphone with a 3.5 mm jack. Can I use this for recording in garage band in my ipod touch. Thanks for the help.
Answer: Not directly - you need, at minimum, a plug adaptor to take the 2-way connector on the mic to the Apple standard 4-way connector.
There are a lot more advanced methods too, involving actual 'live' interfaces designed to do just that - it really depends on what kind of mic it is as to what interface would be best, though if its default connector is a 2-way mini-jack, then my guess would be it's a non-powered electret condenser, which are not always the best for music recording.
I'd consider having a look at some of the IK Multimedia iRig devices or alternatively, just start from this Google search for simpler connectors

Can I use a 3.5mm mic in an ipod touch?


Difference between stored procedures and user defined functions

Question: Can anyone explain what is the exact difference between stored procedures and user defined functions, and in which context each is useful?
Comment: Read [Stored Procedures vs. User Defined Functions in Microsoft SQL Server](http://databases.about.com/od/sqlserver/a/procs_vs_functs.htm) [Choice Between Stored Procedures, Functions, Views, Triggers](http://www.paragoncorporation.com/ArticleDetail.aspx?ArticleID=28)
Answer: This is what i always keep in mind :)

Procedure can return zero or n values whereas function can return one value which is mandatory.
Procedures can have input/output parameters for it whereas functions can have only input parameters.
Procedure allows select as well as DML statement in it whereas function allows only select statement in it.
Functions can be called from procedure whereas procedures cannot be called from function.
Exception can be handled by try-catch block in a procedure whereas try-catch block cannot be used in a function.
We can go for transaction management in procedure whereas we can't go in function.
Procedures can not be utilized in a select statement whereas function can be embedded in a select statement.
UDF can be used in the SQL statements anywhere in the WHERE/HAVING/SELECT section where as Stored procedures cannot be.
UDFs that return tables can be treated as another rowset. This can be used in JOINs with other tables.
Inline UDF's can be though of as views that take parameters and can be used in JOINs and other Rowset operations.

Source http://www.codeproject.com/Tips/286539/Difference-between-stored-procedure-and-function
Answer: A function always returns a value, and can not perform DML statements (INSERT/UPDATE/DELETE).
A stored procedure can not return a value - you need to use an OUT parameter - and can run DML statements.
Advantage of Using a Function vs a Stored Procedure?

Aside from the comparison above, they are equal.  But given the comparison, depending on what you need to do it's likely you will use a stored procedure more often than you will a function.
Comment: You can embed functions into other statements because they return values. Lets you do things like
    SELECT * FROM TableFunction(Param1, Param2) TF INNER JOIN Table T ON T.Key=TF.FKey WHERE TF.Col1=ValueFunction(Param3)
Comment: @eftpotrm: That usage is frowned upon, because you can replace it with a JOIN.  Also, it encapsulates the logic - meaning if used in the SELECT portion that you are running a correlated SELECT, which will execute for every row returned.  Been there, done that, saw how poorly the query scaled.
Answer: User defined function has few limitiations like DML statments canbe used etc pls check
Answer: Differences:

Procedures can accept input(default), output and inout type parameters for it. Functions can accept only input type parameters.
Procedures may or may not return a value or may return more than one value using the OUTPUT and/or INOUT parameters. A procedure may return upto 1024 values through OUTPUT and/or INOUT parameters.
Function always returns only one value.
Stored procedure returns always integer value by default zero. Function return type could be scalar or table or table values.
Stored procs can create a table but can't return table. Functions can create, update and delete the table variable. It can return a table
Stored Procedures can affect the state of the database by using insert, delete, update and create operations. Functions cannot affect the state of the database which means we cannot perform insert, delete, update and create operations operations on the database.
Stored procedures are stored in database in the compiled form. Function are parsed and conpiled at runtime only.
Stored procs can be called independently using exec keyword. Stored procedure cannot be used in the select/where/having clause. Function are called from select/where/having clause. Even we can join two functions.
Normally stored procedure will be used for perform specific tasks.
Functions will be used for computing value. Stored procedure allows getdate () or other non-deterministic functions can be allowed.
Function won't allow the non-deterministic functions like getdate().
In Stored procedures we can use transaction statements. We can't use in functions.
The stored procedures can do all the DML operations like insert the new record, update the records and delete the existing records. The function won't allow us to do the DML operations in the database tables like in the stored procedure. It allows us to do only the select operation. It will not allow to do the DML on existing tables. But still we can do the DML operation only on the table variable inside the user defined functions.
Temporary tables (derived) can be created in stored procedures. It is not possible in case of functions.
When sql statements encounters an error, T-SQL will ignore the error in a SPROC and proceed to the next statement in the remaining code. In case of functions, T-SQL will stop execution of next statements.

Refer this link :
https://www.spritle.com/blogs/2011/03/03/differences-between-stored-procedures-and-user-defined-functions/
Comment: While this link may answer the question, it is better to include the [essential parts of the answer](https://meta.stackexchange.com/a/8259) here and provide the link for reference. Link-only answers can become invalid if the linked page changes. [Answers that are little more than a link may be deleted](https://stackoverflow.com/help/deleted-answers)


Exempt income and Roth IRA contributions

Question: So I am a student and will be making less than 6 thousand dollars this year, and so I'll be exempt from taxes. Can I use some of the money I make to contribute to a Roth IRA?
Answer: If by exempt, you're just referring to the fact that the income is less than your standard deduction and personal exemption, then yes, that money can be used to fund a Roth. Great time to do it.
To be clear, in 2014 the limit for an under 50 year old, is $5500 ($6500 if 50 or older). Only earned income may be used for deposits. No interest, dividends, etc.
Comment: It is worth emphasizing that IRA contributions are limited to the lesser of $5500 and the total "earned income" from salaries, wages, self-employment etc. This needs to be taken into account if any part of that < $6K is from interest or dividends etc.
Comment: Yes! Done. You are always welcome to edit my answers to add such clarifying remarks. Thanks, again.


Why we need topology to define these new form open sets?

Question: By the definition of topology, I feel topology is just a principle to define "open sets" on a space(in other words, just a tool to expand the conception of open sets so that we can get some new forms of open sets.) But I think in the practical cases, we just considered Euclidean space most and the traditional form open set in Euclidean space works pretty well. And these new form open sets seem to have no common use. So why we need to expand the conception of the open sets? What's the motivation behind?Thanks.
Answer: I think your idea that topology is just to define open sets misses the point. I interpret the point of topology as attempting to generalize the concept of a continuous function primarily, and open sets are often the most direct pedagogical route there.
Further, one often does want to leave euclidean space. For example, we often want to consider spaces of continuous functions where the topology (say, pointwise convergence) may not even be metrizable! Topological spaces that are not first countable, and thus not metrizable, also arise quite naturally in functional analysis.
Even at times when one can fundamentally imbedd the space being worked on into some euclidean space, this is often a cumbersome process adding on unnecessary baggage.
Comment: There's a few reasons. One, generalization and abstraction allow one to focus on the core of what is going on and remove unnecessary baggage. More importantly though, spaces show up that are not even metrizable in practical situations. For example, pointwise convergence of functions in function spaces. It would be nice to have a way to discuss this convergence but we can not use our metric space notions as is. Open sets on their own are really not what topology is about, they are important because they let one talk about continuity and limits.
Comment: Thanks,but why do you think "attempting to generalize the concept of a continuous function primarily".In my mind, the definition of topology just tells you what are open sets and their characteristics.
Comment: Thank you very much, it looks reasonable, but a little abstract, could you offer me a concrete example?
Comment: Here, this thread has a number of examples! http://mathoverflow.net/questions/52032/examples-of-non-metrizable-spaces In each instance the space is not metrizable, but we still want to discuss convergence and limits.
Answer: For starters, we have things defined abstractly (at least in principle) such as manifolds. These are defined through charts, which endow your manifold with a topology.
The important tool of partitions of unity (which reduces Stokes's theorem and others to a toy case) works due to the 2nd Countability Axiom (see e.g. Warner, Foundations of Differential Manifolds and Lie groups).
There are important results in Commutative Algebra such as finiteness of irreducible components of the spectrum of a noetherian commutative ring: topology furnishes a proof of an algebraic result (see Atiyah & Macdonald, Introduction to Commutative Algebra).
Also, the topology is kind of qualitative, i.e. you are not considering a particular metric only, but only those equivalent to it (i.e. those which yield the same topology).
There are many more things one could say, but we'll leave it at that until further comments appear.

Where you can see a nice interplay between topology and analysis is in the Gelfand-Naimark theorem:  the maximal rings of the ring of (real or complex) continuous functions over a compact topological space $K$ is homeomorphic to $K$ itself.
Again, a good reference is Atiyah-Macdonald (it's in the Exercises section, if I remember rightly).
Comment: I have just added a comment on a well-known result.  I think the Gelfand-Naimark theorem is a generalisation.
Answer: We need topology so we can work limits. And limits are important.
Comment: What kind of limits we can't work without topology?
Comment: Excuse me? What does this question even means? The definition of limit is based on topology, the definition of converging sequence may be used to define a topology, and in general we can even define a notion of convergence to be equivalent to the definition of topological space. Topology is the idea behind closeness, and practically everything in analysis is about approximation.
Comment: Thanks, you said we need topology to work limits, but topology defines different forms of opens, do we need these different form open sets to work on limits?
Comment: It depends on the problem at hand, but yes. If you want to be able to speak of limits you need first a topology. (Or if you want a topology you may define what converges where.)
Comment: Here there are issues: one may have two limits to a sequence, if we work with a non-Hausdorff topological space.


RFID + permanent magnet

Question: A project I'm exploring requires placing a permanent magnet in close proximity to an RFID tag (within a cm or so). Can an RFID tag be read when there's a permanent EM field so close to it?
Comment: This really does depend on where you put the magnet and what the magnet is made of. This information is needed before anyone can sensibly make a stab of answering unless there is an answer that can cover all the bases of material and position. Certainly, a magnet can help 125kHz and 13MHz tremendously but they can also be positioned or have material content that renders the TAG unreadable. Also, at UHF the magnet could have massive losses and, due to position render the tag useless.
Answer: That really depends on your RFID technology and frequency range you are using.
With LF (125/135 kHz) and HF (13.56 MHz) you will have problems (as they work inductive) due to core losses, i.e., eddy currents (the higher the frequency, the higher the losses) and hysteresis.
You will have more problems with HF than LF. LF tags sometimes have ferrite cores to increase the inductance of the coil.
With UHF tags you may have even advantages, depending on the distance (frequency dependent) and orientation between tag and magnet and the antenna design of the tag. However, there exist UHF tags particularly for use on metal.
Answer: Depends on the tag. LF (125KHz) will certainly have problems. HF (13MHz) might work, depends on the tag's antenna. UHF (850-930MHz) tags will work, depending on their mounting with relation to the magnet. There are tags specifically designed to be mounted on metal surfaces, however I do not have much experience with those.

RFID + permanent magnet


Geometry node spacing along curve

Question: Is there a way to have the bolts instanced along a curve in geometry nodes with proper spacing between one another on each side of the pipe? I want each segment of pipe to have the same amount of bolts on each side.
Answer: The Curve to Points node is really useful for this. If you need even spacing instead of even amounts, change the mode from Count to Length.

This would work on any curve (or multiple curves at once):

The same curves but with mode changed to Length:

Update
What you really need to do to make this work correctly is to create two offset curves based on the original base curve (I'm assuming that your pipe is based on a curve) and then use the Curve to Points node to spread out the instances evenly:
Comment: You can set the Curve-to-Points node to "Length" mode to get even spacing between the points, instead of a fixed count over the whole curve. It will change the total amount based on how long the curve is. This may or may not be what the OP needs, it's hard to tell without more detail.
Comment: @TobiasEinarsson Thank you for another update, this solves my problem. Sorry for all the confusion
Comment: Sorry this is not what I need, I want the bolts along the curve to be evenly spaced not the ones on the connecting peice
Comment: @MasonHeilman Just saw your edit, doesn't the Curve to Points node with Count set to 11 solve your problem? The curve circle is just a representation of your curve, it could be whatever shape. Otherwise, you need to clarify what you're trying to achieve.
Comment: I am talking about the bolts along the length of the tube not the flange, they are closer together on the inner bend
Comment: @MasonHeilman I've updated my answer with another curve as input.
Comment: The photo you added to your post is showing the same issue. the spacing between the bolts is not the same. Say the curve to the left you updated your post with was to make a full circle. There should not be the same amount of bolts on the inner radius as there are on the outside.
Comment: @MasonHeilman Quote from your question: "I want each segment of pipe to have the same amount of bolts on each side." Set the mode to length instead of count if you need even spacing instead of same amount.
Comment: I added an edit showing the nodes I am using. It is set to length. Are you using two different curves
Comment: Yes, there are two curves.
Comment: @MasonHeilman I updated my answer with a node setup that creates two offset curves (one on each side of the pipe) based on the original one. Hope it helps!
Answer: This is a near-repeat of @Tobias Einarrson 's answer since he's edited it (.. the main point being to sample a curve by length). This adds a workflow option, though, so maybe it's worth posting.
Starting after you've made your mesh, somehow, inside  or outside a GN tree.

You can select edge-loops of the mesh to carry the bolts, weighted 1, and add them to a vertex-group.
Feed  that group as an input to an 'Add Bolts' GN modifier

In this example, the vertex-group input as 'Linear':

First of all, the Normal of the underlying mesh is captured.. (curves
can twist undesirably)
Then the vertices with enough weight in the group are separated from the mesh. (Edges are preserved)
The separated edge-segments are converted to a multi-spline curve.
The curve is sampled by length, and the bolts instanced on it.
The bolt-instances are rotated to align with the mesh-surface Normal.

When you sample a curve by length in GN, the endpoints are always included, and the rest are 'best fit'. Which, in this case, IMO, is quite helpful.
The method would work just as well for stitches in upholstery or clothing, ornamental beading.. etc.
Answer: you can use this node setup, to achieve the effect:

The resample curve node with "length" gives you even spaces.
result:

by adding scene time, some map range nodes, you can even animate the bolts:

Geometry node spacing along curve


What are WSDL, SOAP and REST?

Question: What is WSDL? How is it related to SOAP? Where does REST fit in all of that?
Answer: A WSDL is an XML document that describes a web service.  It actually stands for Web Services Description Language.
SOAP is an XML-based protocol that lets you exchange info over a particular protocol (can be HTTP or SMTP, for example) between applications.  It stands for Simple Object Access Protocol and uses XML for its messaging format to relay the information.
REST is an architectural style of networked systems and stands for Representational State Transfer.  It's not a standard itself, but does use standards such as HTTP, URL, XML, etc.
Comment: `"A WSDL is an XML document that describes a web service. It actually stands for Web Services Definition Language."`
This really doesn't explain what it is...
Comment: Representational State Transfer (REST) is an architectural style that specifies constraints, such as the uniform interface, that if applied to a web service induce desirable properties, such as performance, scalability, and modifiability, that enable services to work best on the Web. In REST style, data and functionality are considered resources and are accessed using Uniform Resource Identifiers (URIs). The resources are acted upon by using a set of simple, well-defined operations. it follows client/server architecture and is designed to use a stateless communication protocol,typically HTTP.
Comment: I meant to put SMTP or HTTP as examples of protocols that SOAP can be used over.  I didn't intend it to mean HTTP is the only protocol that can be used (was just using it as an example).
Comment: Isn't the 'D' in WSDL stand for "Description" instead of "Definition"?
Comment: @Sparkzz according to wikipedia:
`The current version of WSDL is WSDL 2.0. The meaning of the acronym has changed from version 1.1 where the "D" stood for "Definition".`
Comment: Why is wsdl needed? REST doesnt need it. Developer can see the documentation. Why is advertising the capability along with input and output argument necessary?
Comment: It isn't needed, it does provide the ability for the developer to automatically generate the client classes they need to interact with the service though.
Comment: A WSDL just makes it significantly easier to manage and auto-generate the SOAP client. WSDL's are essentially the contract between two SOAP endpoints. We can keep them in sync by versioning the WSDL and storing WSDL somewhere publicly available (or secured if required).
Comment: @MinhNghĩa REST is not self-describing, by itself. A SOAP web service with a WSDL is. A REST service with something like Swagger is more or less self-describing.
Answer: Example: In a simple terms if you have a web service of calculator.
WSDL: WSDL tells about the functions that you can implement or exposed to the client. For example: add, delete, subtract and so on.
SOAP: Where as using SOAP you actually perform actions like doDelete(), doSubtract(), doAdd(). So SOAP and WSDL are apples and oranges. We should not compare them. They both have their own different functionality.
Why we use SOAP and WSDL: For platform independent data exchange.
EDIT: In a normal day to day life example:
WSDL: When we go to a restaurant we see the Menu Items, those are the WSDL's.
Proxy Classes: Now after seeing the Menu Items we make up our Mind (Process our mind on what to order): So, basically we make Proxy classes based on WSDL Document.
SOAP: Then when we actually order the food based on the Menu's: Meaning we use proxy classes to call upon the service methods which is done using SOAP. :)
Answer: Every time someone mentions SOAP/WSDL, I think of objects and classes defined in xml...

"You use SOAP just the same way that you would any PHP class. However, in this case the class does not exist in the local applications file system, but at a remote site accessed over http."
...
"If we think of using a SOAP service as just another PHP class then the WSDL document is a list of all the available class methods and properties. "
http://www.doublehops.com/2009/07/07/quick-tutorial-on-getting-started-with-soap-in-php/comment-page-1/

..and whenever someone talks about REST I think of HTTP's commands (request methods) like POST, GET and DELETE
Answer: SOAP -> SOAP(Simple object access protocol) is the application level protocol created for machine to machine interaction. Protocol defines standard rules. All the parties who are using the particular protocol should adhere to the protocol rules. Like TCP, It unwinds at transport layer, The SOAP protocol will be understood by Application layer( any application which supports SOAP - Axis2, .Net).
WSDL -> SOAP message consist of SoapEnevelope->SoapHeader and SoapBody. It doesn't define what would be message format? what are all the transports(HTTP,JMS) it supports? without this info, It is hard for any client who wants to consume the particular web service to construct the SOAP message. Even if they do, they won't be sure, it'll work all the time. WSDL is the rescue. WSDL (Web Service description Language) defines the operations, message formats and transport details for the SOAP message.
REST -> REST(Representational state transfer) is based on the Transport. Unlike SOAP which targets the actions, REST concerns more on the resources. REST locates the resources by using URL (example -http://{serverAddress}/employees/employeeNumber/12345) and it depends on the transport protocol( with HTTP - GET,POST, PUT, DELETE,...) for the actions to be performed on the resources. The REST service locates the resource based on the URL and perform the action based on the transport action verb. It is more of architectural style and conventions based.
Answer: You're not going to "simply" understand something complex.
WSDL is an XML-based language for describing a web service. It describes the messages, operations, and network transport information used by the service. These web services usually use SOAP, but may use other protocols.
A WSDL is readable by a program, and so may be used to generate all, or part of the client code necessary to call the web service. This is what it means to call SOAP-based web services "self-describing".
REST is not related to WSDL at all.
Comment: Uhm, if you can use it for other protocols too, why does no one describe REST-APIs with WDSL?
Answer: SOAP stands for Simple (sic) Object Access Protocol.  It was intended to be a way to do Remote Procedure Calls to remote objects by sending XML over HTTP.
WSDL is Web Service Description Language.  A request ending in '.wsdl' to an endpoint will result in an XML message describing request and response that a use can expect.  It descibes the contract between service & client.
REST uses HTTP to send messages to services.
SOAP is a spec, REST is a style.
Comment: Are you saying that you can't do RPC with SOAP?  I know that might not encompass the entire standard, but it was certainly the original motivation.  As far as whether or not the WSDL URL is part of the standard, I'll admit that you have me there.  It's usually the way I see it done, but I can't cite anything in the standard that mandates it.
Comment: -1: sorry, but I disagree with associating SOAP with RPC. What about message-style services? Also, there's no standard that says a request ending in .wsdl or ?wsdl will generate a WSDL.
Comment: You may have been confusing the fact that SOAP was derived from XML-RPC with the idea that SOAP was originally intended as an RPC. Yet note that WSDL, from the start, was able to describe document-style services, in addition to RPC style services. If RPC were the original motivation behind SOAP and WSDL, then one would expect that document-style services would have been absent from the original standard.
Answer: Wikipedia says "The Web Services Description Language is an XML-based language that provides a model for describing Web services". Put another way, WSDL is to a web service, as javadoc is to a java library.
The really sweet thing about WSDL, though, is that software can generate a client and server using WSDL.
Answer: REST is light-weight in terms of encoding, much more useful for light weight devices i.e. non strict APIs.
REST is format independent. XML, HTML, JSON all options are available.
REST provides abilities for on 2 point message transfer (not surprising since REST stands for REpresentational State Transfer) where WSDL/SOAP interaction is multiple point message interaction.
REST does not require a new extension for XML messages, where in WSDL/SOAP this is the case.
WSDL/SOAP uses multiple transport protocols, REST relies on only HTTP. Therefore WSDL/SOAP can be used like a RESTful way, however simple requests can be overly complicated/heavy weighted.
A simple analogy: REST is like a motoboy delivers your food easy and quick. XML extended WSDL/SOAP more like UPS delivery, more structured and serious stuff but comes with a cost.
Answer: Some clear explanations (for SOAP and WSDL) can be found here as well.
Difference between a SOAP message and a WSDL?
Answer: A WSDL document describes a webservice. It specifies the location of the service and the methods of the service using these major elements:
 data types using in webservice
 data elements for each operation
 describe the operations that can be performed and the messages envolved

SOAP (Simple Object Access Protocol) is a messaging protocol that allows programs that run on disparate operating systems to communicate using http and xml.

What are WSDL, SOAP and REST?


Why PIcklistValues is empty?

Question:
I use a '/services/data/v41.0/tooling/sobjects/RecordType/'.
But picklistValues is always empty, I need it to edit from code
Comment: What is your picklist field name? @Denis Titarenko
Comment: @RuklaniAttanyake 'Job Title'
Comment: Did you make any picklist values for the field within that record type?
Answer: This worked fine for me:
I opened up the Rest Explorer in workbench (logged in to dev org as admin) and executed a GET request using the following URI
/services/data/v41.0/tooling/sobjects/RecordType/0125Y000000BhfpQAC
This returned picklist values:

Perhaps you cannot see the fields because of field level security for the fields? Ensure the user you are logged into Workbench with has Read Access to the field(s) in question.
If they dont, then grant them read access to object and field (permission set / profile level) and then retry your request.
UPDATE: I tried by creating a custom object and custom picklist field like yourself, and got the same results (no info on picklist field/values)
You can access picklist values by using a describe call:
<code>/services/data/v23.0/sobjects/<sObjectName>/describe
</code>
maybe you can use that instead?
I did find this question: Retriving all Active picklist values of all recordtypes
the answer says:

Unfortunately, picklist + record type information has very uneven
coverage across Salesforce APIs

That answer also says you can use the UI API to retrieve the picklist field values. I tried this and it works with the custom object. Try the following:
<code>/services/data/v42.0/ui-api/object-info/<ObjectApiName>/picklist-values/<your record type id>
</code>
this returned the following:

As for using the Tooling API call, Sorry I could not answer further, but same call works for Account and fails for custom object. Seems like this is an inconsistency on Salesforces side. Maybe open up a ticket with them to get a more fruitful explanation?
If anyone else can identify the reason I would also love to know why this is happening.
Comment: Thanks for answear! I have permissions to read this fields. I also see picklistValues on objects like Task, Account etc.
Comment: @DenisTitarenko I updated the answer above, hope that helps you out

Why PIcklistValues is empty?


How can the child of a convert know/find out if the conversion was valid?

Question: A non-Jewish woman converts to Judaism, marries a Jewish man, and has children.  She has told her children that she was converted by an Orthodox beit din, to be sure that her children are all recognized as Jewish, even in the state of Israel.  The woman has died, and her widower is old and has cognitive problems and can't remember details about the conversion.  How can the children find out
- where/by whom she was converted
- whether her conversion is valid, recognized, and binding
- whether the State of Israel will recognize the children as Jewish.
Comment: Welcome aboard @Rebeccah. It's a good question and one that many people are confronted with particularly when approaching marriage. Regarding the where and by whom part of your question, if you can't get your hands on their ketubah, the best bet would be to look at what community they got married in. In America, if you are going back more than 30 years, records are going to be hard to find. Regarding 'recognition', you should be consulting with whatever Beit Din you are dealing with. They will be best able to advise you about what is acceptable in their jurisdiction.
Comment: detective work is needed
Comment: We're going back about 60 years.  I'm not dealing with any beit din at this point, but the father's confused memory and what I was able to dig up at the time this came up suggested that it might have been a conservative rabbi that oversaw her conversion, not an orthodox one.  And now I can't remember the name of the rabbi any more.
Comment: You really shouldn't look into it unless you have to. Rav Moshe was very against even for baalei teshuva to not look into genealogy. Don't create problems
Answer: There should be documentation as to which bais din did it and when along with the kesuvah since the rav who married them would have verified the situation. Check the location where the kesuvah is stored.
Also check with the rav (if he is still alive) or whoever now has his records. Many rabbis have sent copies of their records to the Rabbinical Council of America. If the rabbi is no longer available, the records of the wedding would be kept with the synagogue of that rabbi or turned over to his successor.
The kesuvah will ordinarily have been kept by the married couple and may be with the documents such as the wills.
I had encountered a similar situation many years back in Israel and the woman did a gerut (conversion) misafek (from doubt) to make sure everything was valid. While it would be a hassle it enabled her to marry in Israel. The RCA could help with that if no documents were found
Comment: The ketubah, if one exists,  is unfortunately nowhere to be found, and definitely not with the wills.  The couple was initially married in a civil ceremony.  I think the conversion took place after they were married.  Supposedly they had a religious ceremony later, but I've never seen any documentation from it.  If one of the children were to make aliyah and want to get married in Israel, would there be a problem?
Comment: Anyway, thanks for the suggestion to check with the rabbi's successor (I tried Rabbinical Council of America a few years ago and they were of no help).  Googling the synagogue's history, I was able to recall the name of the rabbi, and I've sent off an e-mail to the current rabbi.  We'll see if anything turns up.
Comment: @Rebeccah I had encountered a similar situation many years back in Israel and the woman did a gerut (conversion) misafek (from doubt) to make sure everything was valid. While it would be a hassle it enabled her to marry in Israel. The RCA could help with that if no documents were found


Order of valves in a trumpet

Question: I'm re-furbishing an old French three valve trumpet. The valves have been mixed up. There are no numbers on them, unlike modern trumpet valves. Is there a simple way to ascertain which valve goes into which aperture?
Comment: Are they piston or rotary valves?
Comment: @Phoog - ordinary pistons.
Answer: Take all the valves out. Then place one of the valves in the third valve casing. Turn it until the valve guide "clicks" then blow (gently!) into the horn. If air goes through, then depress the valve and blow (gently!) again. If air goes through, you have the right valve in the third casing. If air doesn't go through, try the next valve in the third casing...
Once you've got the third valve correct, leave that valve installed and try one of the remaining valves in the second casing. You do them in this order because the leadpipe goes to the third valve and the bell pipe comes out of the first valve.
Be sure to blow gently so that you don't injure yourself if the air stops.
Comment: I was going to say this as a joke!  I.e.,  "play the horn and if the wrong notes come out you goofed"  .  Congrats on being polite about it
Comment: Exactly this. I had to use it myself some years ago at a brass band rehearsal as my section mate's wife had cleaned his tuba and just stuck the valves back in any old how! The night before a contest as well! Being a traditional British 4 valve Eb tuba with 3 on top and one on the side, the 4th valve was easy, then it was just a case of getting the 1st valve correct, then the 2nd.
Answer: I would first try to align the holes in the valve body with the tubes entering the valve housing.  If I recall correctly I've done this successfully with piston valves in the past, but it would have been the fairly distant past so my recollection could be faulty.
If that doesn't work for some reason, you can just try all possible combinations until you find the right one.  There are only six possibilities; it shouldn't take too long.
Answer: The simplest way is to address the second (middle) valve first. Take off the short tube attached to the trumpet (the one which lowers the pitch by one semitone), so you  can see the holes in each of the valves as they are put in, in turn. Only one will have holes which line up with those in the trumpet pipework, when depressed. That, then, will be the appropriate no.2 valve.
Then, it's 50:50 for the other two!
Comment: This, of course, assumes that (a) it is possible to get the tube off, and (b) once off it's possible to see the valve holes. Of the instruments I could immediately lay my hands on the success rate was 50:50, which is not bad :)
Comment: @psmears - the tube ought to be removable - I'm refurbishing, and if not, the job's not a good'un. Yes, it's quite possible to see the valve  holes, hence the answer. Point is, it's only possible to see the holes on valve two.
Comment: Yeah - on one of the instruments I looked at just now, the middle tube is mounted at an oblique angle, so it's unclear whether removing it would give a clear enough view of the holes. Unfortunately it's also wedged on tight (and I don't have time to unwedge it), so I wasn't able to actually check...
Comment: @psmears - all three should be easily removed. When that one in particular is removed, one can see the holes line up. Not so with the other two.
Comment: "Should"? Yes! (at least in this case - wouldn't surprise me to find a low-quality instrument with them welded on). Just needs some TLC that I don't have time for. "See the holes"? In this case I'm not sure, because there is a (designed in, deliberate) bend in the tubing between the joint with the valve and where the loop slides off. (On the other instrument I looked at there's no such bend; the tubing slid off easily and the valve holes were clearly visible. My point is that there's a surprising amount of variation in instrument design and quality, which may make some approaches less useful.)
Answer: There's only six possible combinations!   Just try.  Put one of the valves into the first housing.  Blow.  If air doesn't get through with the valve both up and down try one of the other two.  Then the next housing...

Order of valves in a trumpet


How to make the most of your companions?

Question: How can I make the most out of my companions in Diablo 3 ROS? I realize they won't be doing as much damage as I do, but I've chosen their perks, I keep their weapons and gear updated as best I can, but they still feel useless to me, and even at level 55, they're not helping me much in terms of DPS.
Comment: The companions are helpful more for healing and crowd control more than for dps.
Comment: It also depends what class you are. Some companions work better with certain classes. i.e. My Wizard really benefits from the Templar because of his tankiness and healing. I don't count on my companion for any DPS.
Answer: There are many ways to benefit from your followers. Even though they don't deal much damage, they can offer you some good support utility.
1 - The Enchanteress
Skills

Charm, Disorient and Mass Control allow you to benefit from effect versus ennemies under control imparing effect (like Bane of the Trapped).
Missile Ward and Powered Armor both offer some welcome and free toughness.
You can get more damage for free with Erosion and Focused Minds.

Items

Maximus will allow you to get a Sumonned Demon.
The Tormentor has a chance to charm ennemies on hit.
The Grand Vizier : in its legacy version could roll with high (up to +50%) magic find and gold find. So a nice bonus for you.

2 - The Scoundrel
Skills

Crippling Shot, Dirty Fighting and Powered Shot offer some Crowd Control, once again helping to trigger items like Bane of the Trapped.
Hysteria or Anatomy will boost your damage for free.

Items
There is only one item I'd recommand to get on Lyndon and it is : Buriza-Do Kyanon. This items synergizes very well with his skill Multishot. Each arrow he shoots has up to 10% chance (15% if you have a legacy version of Buriza) to freeze the target on hit aswell as piercing thus hitting and freezing foes behind too. Thanks to multishot Lyndon shoots 3 arrow at a time so you can imagine the potential for this combo. You can even add (if you find it) a legacy version of The Star of Azkaranth which would boost his chance to freeze on hit to 20%. Thats a huge Crowd Control boost.
3 - The Templar
My favourite because it offers my class (Demon Hunter) some welcome sustainability and is aswell a permanent Crowd Control source if used correctly.
Skills

Heal, Loyalty and Inspire bring some welcome sustain for life and ressource (especially in Greater Rifts)
Charge offers some welcome Crowd Control and will make the Templar go in melee range and take the aggro of the mobs which can be very helpful.

But for me the Templar shines with a special combo :
Intimidate : This skill allows you to have almost permanently slowed ennemies arround the Templar. If used with Bul-Kathoss' Wedding Band (a ring that drains life from, and so inflict damage to, all enemies arround you) in duo with Thunderfury (the lightning bolt has a huge range and allows the Templar to aggro mob from very far and still slow them by 80% for 3 second). Using this method you can benefit from items like Bane of the Trapped or skills like Cull the weak permanently without having to think about how to slow your foes.
4 - In general
You can get the following items on any follower :

The Ess of Johan will occasionally (often enough for you to notice) pull all enemies toward the target of your follower. This can be helpful to group up mobs in the same place and use your AOE more effectively.
Overwhelming Desire has a chance to Charm ennemies on hit and they also suffer from 35% more damage. It doesn't work on Boss though usefull enough on elites for you to use it.

Last but not least : the most used trick with followers is to have both you and the follower use Unity and put a Follower items that makes him invulnerable (The Focus, The Relic or The Token). The actual effect of those items are Your follower doesn't take damage anymore. This implies that when the follower gets hit he takes 0 damage so the Unity's effect doesnt affect you. However when you take damage, 50% of those damage are redirected to the follower who doesn't take any. That's a net free 50% damage reduction.
Comment: This is really helpful, but ChaseC is right, I don't think I've ever found any of those items (save for a low-level Thunderfury on my HC Crusader). But definitely a good guide!
Comment: Great write up, but to make this answer truly amazing would be to take out the legacy items and put in the new legendaries.
Comment: Well I guess you're right for the Star of Azkaranth which mlight be very hard to find. However the other 2 (Grand Vizier and Buriza) still stands. The buriza still rolls with up to 10% freeze on hit chance (not 15% but still) and the Grand Vizier can still roll high GF. All the other item mentionned are obtainable at present through looting/gambling at Kadala :D
Answer: To "get the most" out of your Follower (a bit different than a companion which is the term for a Demon Hunter's friendly animals that are enabled by a skill or Marauder's set) you have to reconsider what their usefulness is.
Many players will tell you, trying to maximize a Follower's DPS is all in vain, as their DPS is only a pittance of your main character's ultimate capabilities. In fact, by the time you are level 70 and start working on 'min-max'ing a build, your Follower will only do a fraction of a percent of damage that you can, even with the absolute best items.
Instead, you have to focus on support abilities and legendary item combinations that can turn the tides.
For most players, the most useful Follower, is one who sports a Unity ring with a Token that has the legendary ability of "Your Follower cannot die". Couple this with a Unity ring on your own character and that is the most usefulness you can get out of a Follower as they will effectively mitigate 50% of your taken damage.
There's other tricks you can do with Followers also, but most fall short of being efficient.
Comment: Also, item combinations like wyrdward and the thunderfury (wieldable only by Kormac) can help stunning enemies frequently.
Answer: Get 2 unitys(share 50 % dmg with whoever else has this ring, including your follower) one for yourself and one for your follower. Then get the trinket on the follower ( whichever you get first ) that they cant't die. Proceed to enjoy 50 % permanent DmG reduction.


PLS-DA for varible selection and then LDA for classification

Question: I have been trying to do classification of my hyperspectral data. The variable selection were done with variable importance in projection in pls-da. The selected variables were then used for classification, but in pls-da it did not show any clear separation. However when the selected variables were then analysed with lda it showed clear separation. Now I am not sure is it statistically correct to use the variables selected with pls-da and the classification done in lda.I have read that variable selection done with pls (not with pls-da) and then classification with other methods.
Answer: PLS and PLS-DA are very similar methods. In particular PLS-DA is simply PLS with dependent variables being categorical. Thus, selecting variables with PLS or PLS-DA for classification is equivalent.
I do not expect a huge difference in model performances among PLS-DA and post-LDA.
In the case of multicollinearity or if the presence of unrelated variables are suspected, one may want to select the best variables for LDA. It is not incorrect and may work very well in some cases.
However, I personally find variable selection methods based on regression coefficients, VIP scores, loadings unreliable to cope with multicollinearity problem, especially if your aim is improving model accuracy rather than simplification of model. Even if multicollinarity is not the issue, I would give PLS-LDA a try before variable selection. (see this link). Since all the variable selection methods can be somewhat dangerous and may lead to overfitting, testing the model against a independent validation set is a must.
Comment: It was helpful. I am using the softwares like past 3 and SIMCA-P+ softwares. I used SIMCA for the pls-da.It does not have lda. Then I read about the software past which was user friendly. From SIMCA I got the VIP from pls-da and those varaibles were selected and used for lda in past.  I am learning R now and try pls-lda in R.
Comment: collinearity was the issue in this case. why would it be so that pls-da didnot show any separation but lda showed a clear separation.
Comment: have you tested your models on an independent validation set?
Comment: I have done the cross validation with 10-fold cross validation


Linux mint 13 - Update to mint 17 faillure

Question: I've tryed to update my system (linux mint 13 to linux mint 17) using this procedure (https://www.linuxtricks.fr/wiki/mettre-a-niveau-linux-mint-vers-une-nouvelle-version) and doesn't work.
Now I only have acces to windows 7 (once the system is on dual boot) but the GRUB shows the lines with LINUX MINT 13 188.8.131.52 - generic (/dev/sd5)
If i click on this option i see a small window to put my login and password and then i have the message saying that "cinnamon, not present".
Anyone have an idea how can i repair it? Thank you for yours answers.
Answer: Hard to say, but you may try to boot from a live USB then do:

either boot-repair https://help.ubuntu.com/community/Boot-Repair
or grub-install http://howtoubuntu.org/how-to-repair-restore-reinstall-grub-2-with-a-ubuntu-live-cd

Best of luck
Comment: He can boot, he can't access his DE, apparently.


Changing URL - how harmful is it

Question: We have a very old site with lots and lots of content. We are considering changing our URL because the current URL was a vanity URL and does not represent the company in its current form. How
Answer: If it doesn't represent who the company as it is now then you should definitely use the new URL and have a splash page on the old URL with a link to the new website (avoid instant redirects because people may then think your new website is just spam) with a brief explanation why you are doing it and that all services on the old website are on the new one (or something alike)

Changing URL - how harmful is it