Xcode 4.2.1 Code Folding

Question: I've got a really frustrating issue in Xcode 4.2.1 on OS X Lion, where the code folding doesn't seem to work, or at least hardly every with no obvious reason.
The default keyboard shortcuts are supposed to be:
<code>Fold Methods/Functions      ⇧⌘⌥⌘←      shift+option+command+left
Unfold Methods/Functions    ⇧⌘⌥⌘→      shift+option+command+right
</code>
.. but I just get the Homer ('Doh'), error sound all the times I try it.
I always make sure I have the correct pane selected (before anyone asks ;o), and have also tried the following, with no luck:
<code>- With & without Assistant editor enabled
- In a total separate editing window
- By selecting 'Code Folding >> Fold Methods & functions' from the Editor menu
- Changing the keyboard shortcut (Even tho no conflict was showing)
</code>
The only clue I have, and I'm not sure if it's related, is that whenever I press the 'option' key in the editing view my cursor changes to a + (or crosshair) - It only does this in the editing views of Xcode, however I don't think this is the issue as if I change the shortcut to not use the 'option' key, it still doesn't work.
Anyone got any ideas, as it's driving me barmy & my searches haven't come up with anything??
Answer: OK, I finally resolved to totally remove Xcode, clear out prefs and then re-install.
This seems to have fixed the issue (So far at least)
Answer: I've found that Xcode 3 won't fold unless syntax highlighting is turned on. I don't like syntax highlighting, so for lack of a better alternative I use 'View->Syntax Coloring->Simple Coloring', which only highlights comments and numbers.

Xcode 4.2.1 Code Folding


How to get official confirmation if anyone has filled a police complaint against me or not

Question: My wife has alleged that she made a police complaint against me in Germany for a false domestic violence case. Is there a way to find out if any complaint has truly been filed against me or not if I don't live in Germany anymore?
Comment: Related: https://law.stackexchange.com/q/78288/35069
Comment: Note that in Germany, police is a state matter. Each Bundesland will have its own laws and own procedures governing such information. However, the EU Law Enforcement Directive does lay down basic privacy rights, including a right to access information the police holds about you, as long as disclosing that information to you wouldn't jeopardize ongoing investigations. It can take 3 months or more to get a response.
Answer: You can query the Zentrales Staatsanwaltliches Verfahrensregister regarding your own cases once they reach that level. I'm not sure how this works out if you are no longer in Germany, since you would have to prove that you are yourself. As I understand this site, they expect you to send a postal letter rather than a mail.
There is no guarantee of getting a complete answer. Investigations may be tagged as 'secret' to avoid warning the criminals. That would usually not be the case in a domestic violence investigation, but it is more common in organized crime cases and the like.
Comment: Thank you. I will try this.
Comment: Note that the request will almost never show up inquiries of Verfassungsschutz in the early stages  and absolutely never those of the Abschirmung.
Answer: You can ask for a "Selbstauskunft". I have no idea how you would get one, and what it costs, but the police would know. That would contain everything the police has on file about you (only you yourself would be able to get that information, everyone else would get something redacted).
If your wife's complaint was serious enough to be written down it would be there. If she went to a police station, made a complaint, but let it slip to the officer that the complaint is false and only made to get you into trouble, then it might not ever have been recorded. That means legally the complaint doesn't exist.
Comment: Actually, the police don't have to tell suspects everything they have. That would defeat such things as phone taps and undercover cops ...
Comment: Thanks. I will also try to get this. I just want to know whether there is anything on record or not. If it's not on record then I just need some proof that there is nothing on record in Germany.
Comment: @GoodKarma, no such proof, see above. Only that Germany does not *officially admit* that there is something ongoing. Also, do you know the *Führungszeugnis*? You can request an official record of your recorded convictions, e.g. if you want to work in sensitive areas. But there as well, official agencies will get more than the citizens/residents themselves.
Comment: @o.m. Thanks. Yes, I heard about Führungszeugnis but that is a conduct certificate right? I am not sure whether I should apply for Selbstauskunft or Führungszeugnis. If at all a complaint was filled it would have been filed more than a year ago. So I guess their inquiry stage must be over.
Comment: @GoodKarma, a *Führungszeugnis* contains convictions, not investigations. But an inquiry would remain open if the police were suspecting you of a crime and could not find you, depending on the severity of the charges. The thing which makes me hesitate in my answer is that you left Germany. If you were still living in Germany, one could say with high confidence that you would have received mail from the prosecutor's office or the police if there was anything to the charges. If you are in their files as *unbekannt verzogen*, the case may be gathering dust until they have your address again.


How to export from Illustrator to Photoshop ensuring quality as much as possible?

Question: So i have this picture
, and I want to export it to Photoshop such that it is as close as possible to the original vector in illustrator. However, I get this when exporting to psd with write layers, with the picture being not smooth enough for further development? So how do I get this done?
Comment: You can click and drag an AI file directly into Photoshop.  No need to convert it.  It will automatically become a Smart Object, which will still be editable in Illustrator.
Comment: Illustrator will rasterize the paths when exporting as a Photoshop file. What are you trying to do in Photoshop with the Illustrator file?
Comment: I am trying to make some additional effects to the image in photoshop, so I need to preserve quality, if I understood your question correctly.
Answer: One answer is: You do not
Ok, This probably will not solve your problem, let's go a bit deeper.
In general terms, the idea is to prepare an asset that you need in Raster format and then assemble them in a Vector program.
If your image is already in vectors and it is ok as it is, it "should" remain in vectors.
But this is probably not your case, where you (probably) want to retouch your image and add some effects.
Ok, you need to
Let us analyze first: Do I?
Can you add the effects you need in the Vector program? Can you duplicate your object to have vector elements and raster effects?
YES I need to!
Ok, ok... then simply export to the proper resolution... >:o) (evil face here) Muahaha, this is the tricky part!
What is the real proper resolution you need?
In general terms, for print you export at the real size at 300PPI, yes the image could start viewing some unwanted blurriness but as this is really a necessary step it is probably good feedback that the design will NOT work as you intended.
In the case of your image, you need to define if you want the horizontal lines to be razor-sharp or not.
On a commercial print when you rasterize them they will be screened at an 45° angle so they will be blurry, (that is why you need to leave them as vectors)
For screen, you need to define the real spacing of them. You probably want them razor-sharp on screen, then you need to decide if they will be exactly for example 3 pixels width and 3 pixels spacing.
If you simply choose a random size to work with and a random export setting some lines will be aliased, some will have a gray line of pixels, some will have more space than others. Then try to work in the vector program with some pixel-perfect preview and snap.
These are two examples of why this is a tricky part of designing assets.
One last resource
Is simply to export at a much higher resolution than you probably (or probably will not) need, let's say at 300%, retouch happily your image, play with effects in Ps, and do not worry about the output until that day comes, and live happily with the result even if it is not perfect.
Answer: Just open the Illustrator file in Photoshop
First, make sure your file is saved with PDF compatibility turned on.

Then open the AI file in Photoshop. This can be done either through the open menu, or just by dragging the AI file onto the photoshop application icon. You'll be asked what you want to do with the file. Select the artboard you want on the left, set the dimensions as you want, and then choose your import settings. I recommend using the following settings:

Crop To: Art Box (unless you've sized your artboards to fit your art, in which case select Media Box)
check Anti-aliased
300 DPI
choose RGB or CMYK depending on the color mode you have set in your Illustrator document

Presto! You now have a flat raster to which you can apply effects
A less straightforward approach would be importing the AI file as a smart-object into a photoshop layer, but that's finnicky and results in a larger PSD file.


Scaling and point of origin

Question: I am following the blender tutorial on YouTube, where he creates an anvil. In part one he extruded a cube up, then did a loop cut and scaled it in. When I extrude, my axis moves up with the extrusion and when I go to scale it, it pivots from a corner rather than the center of the model.
How do I get my axis point with the green, blue, and red arrows to stay at the bottom where I started the plane?
Also how do I scale from the center rather than from a corner?
I am just getting started on blender,  and I am used to solid works.
Comment: You have it. 'Pivot Point'. Either by using the button in the header, or '.' (period) on the keyboard, bring up the menu which allows you to choose the pivot point for your transformations. Most of the names are self-explanatory, play with them for long enough to become very familiar with them, both in Object and Edit mode.
Answer: These commands should help:
"Set Origin"
  here you have several options in Objekt mode to place your origin
"Snap Cursor to Active" + "Median Point Menue": 3D Cursor
  here you can change your origin while beeing in Edit-Mode for
  scaling from percise points

Also you should look into the realation between Edit and Objekt mode:
Editmode transformation dont change the Objekt-Mode origin.

Scaling and point of origin


What is accelerated years in describing the amount of the training time?

Question: As described in this article, it was written that GPT-3 took 405 V100 years to train in 2020.
I'm a bit confused about this definition, does that mean the process was accelerated like using a V100 GPU to train in 405 years?
Answer: The statement in which you mentioned that "GPT-3 took 405 V100 years to train" refers to the computational resources utilized in training the GPT-3 model. Specifically measured in terms of the equivalent time it would take if the GPT model is trained on a single Nvidia Tesla V100 GPU. To make it more understandable it does not mean that the training process took 405 years, but it indicates the computational intensity or amount of time it would have taken if it was trained on a single Nvidia Tesla V100 GPU.
Since GPT-3 is a very large model with 175 billion parameters, it requires very high resources in training. According to this article it takes around 1,024 Nvidia V100 GPUs to train the model, and it costs around $4.6M and 34 days to train the GPT-3 model.


What is predicted to happen for electron beams in the Stern-Gerlach experiment?

Question: The Stern–Gerlach experiment has been carried out for silver and hydrogen atoms, with the result that the beams are deflected discretely rather than continuously by an inhomogenous magnetic field. What is theoretically predicted to happen for electron beams?
Comment: @Shinekk Your best best bet is to find the Stern-Gerlach's paper and read what was their motivation for doing the experiment.
Comment: Jerry, you should be surprised:-) It is not feasible to do SG with electrons, since they will deflect away due to Lorentz force.
Comment: They get split by spin... the Stern-Gerlach experiment is most commonly explained in terms of electrons (and I would be surprised if it wasn't originally carried out with electrons)
Comment: @JerrySchirmer I don't think it's ever been carried out for electrons, hence the question but I could be wrong as usual ;)
Comment: But the question is, what did they expect, I heard two different answers, one said that they expected a gaussian distribution (which I doubt), the other say that they expected 3 dots, because they thought, ground state was $l=1$ state. @JánLalinský
                        https://physics.stackexchange.com/q/565433/226827
Answer: Electron beams cannot be split by a stern Gerlach apparatus, because the spin splitting and the orbital splitting cannot be practically separated. The orbital splitting in a constant magnetic field is exactly of the same magnitude as the spin splitting, meaning that the spin anti-aligned electron in a given Landau level is more or less precisely degenerate with the spin aligned electron in the previous Landau level. This means that you can't separate the velocity deflection of the electron from the spin deflection.
This is why Stern Gerlach experiments are only done on atomic beams. There is no simple practical known way to correct for this.
Comment: The question is different
Answer: The splitting of the beam by the Stern Gerlach apparatus is one of the great myths of modern physics. The orignial experiment wasn't done with a pencil-shaped beam but with a fan-shaped beam. While it is true that the fan-shaped beam is split in two, the case of the pencil-shaped beam is quite different. I analyze it in this blog posting. The actual result for the pencil beam is a donut shape. I don't believe there is any way to get just two dots on the collection screen the way people always describe it.
Comment: There is a simple way. [Here](http://i.imgur.com/x3QLkME.gif)'re the animated results of a numerical computation of a gaussian two-dimensional spin-1/2 neutral particle in a Pauli equation, evolving in a Stern-Gerlach magnet magnetic field. If interesting, I can give the C code for generation of $\vec H$, $\psi$ and other parameters.
Comment: Okay, you can get two dots if you use a numerical computation. I meant you can't get two dots if you try to do the actual experiment.
Comment: Why not? Supposedly, Pauli equation should give what experiment gives (for non-relativistic spin-1/2 particles), otherwise it doesn't work, which would be a discovery.
Comment: I did, and it clearly contradicts my observations. I also did the numerical experiment with fan-shaped "beam". It shows the result of Stern-Gerlach very similar to that given in their original article. I.e. the beam splits at the center and doesn't at the borders. (I'll make a picture if you want.) Actually, if the fan is wider, then there's a splitting in another direction on its continuation. And I used the field, directly calculated for the [similar magnet](http://i.imgur.com/muMLNXy.png). Nothing in these numerical experiments supports your claims.
Comment: But I didn't make any claims about the results of numerical experiments.
Comment: The theory (which I used for numerical computation) is supposed to match real experiment. Your statement implies that the theory is plain wrong. But it hasn't been really proven wrong in any real experiment.
Answer: There is a bit of trouble with using electrons since the magnetic field of the apparatus will cause them to turn thanks to the Lorentz force.  You could, of course, build a device to account for the turning, and still split the electrons by spin at the end.
Comment: No you can't build the apparatus to do this, because the orbital splitting can't be separated from the spin-splitting, because of the  degeneracies in the Dirac equation.


How does price decrease when supply increases?

Question: According to supply and demand, when there's an increase in supply, resulting in a surplus, the price falls till it reaches equilibrium. But how exactly does this work? Let's say the equilibrium is 200 widgets at 100 dollars each. I produce 300 widgets to sell them at 150 dollars each, but the problem is people will only demand 100 widgets at 150 dollars each. This will cause a surplus. Am I supposed to lower the price of each widget to 100 dollars (the equilibrium price)? If so, I will only be able to sell 200 of my 300 widgets, leaving 100 widgets left over. What do I do with the remaining supply?
Answer: It's your choice. You could dump them in the landfill. Economists generally assume that you won't dump them in the landfill, and you would rather sell them for some money than no money, therefore you will lower the price until you sold them all.
If that means lowering the price below what they cost to make, then you made too many and next week you will make less. Or (more likely) you will try to balance it out by storing them in a warehouse and selling them next week instead of this week, which is equivalent to producing less this week and producing more next week.
And if many competing firms do these sensible things, the price will end up being the equilibrium price. If there isn't sufficient competition, a monopoly firm may find it more profitable to reduce supply by dumping its product in a landfill or store them in a warehouse indefinitely. Then the price will end up being the profit-maximizing price for that firm.
Answer: You can't just make up arbitrary equilibrium price at the same time as you are making arbitrary supply and demand. Equilibrium price is a price at which supply equals demand. What you are saying is equivalent to saying if $d=rt$ (distance equals rate time time), and I assume rate is 10 km per hour and time 1 hour, how come I have travelled 20km? Well the answer is that you simply concocted impossible scenario, either you cannot travel at that speed or you could not traverse 20km or you had to travel more than 1 hour.
Similarly you can't just make up equilibrium price. Equilibrium price will be the price $p^*$ at which $D(p)=S(p)$. For example, if demand is $D=100-p$ and supply is $S=10+p$ then equilibrium price is $p^*=45$. You can't just say lets say the equilibrium price is 100 (or to be more precise you could say that but in that case you can't also arbitrarily select some demand and supply not consistent with equilibrium price).
Hence you cannot say that equilibrium is 200 widgets at 100 dollars each.

If so, I will only be able to sell 200 of my 300 widgets, leaving 100 widgets left over. What do I do with the remaining supply?

In the case you would either have to reduce price (until you reach actual equilibrium price) to sell all 300 widgets, or just produce less widgets (change supply).
Comment: "*You can't just make up arbitrary equilibrium price at the same time as you are making arbitrary supply and demand.*" Not sure what is wrong with the numbers given in the example. Outlined demand could be $D(p) = 400 - 2p$, supply could be $S(p) = 2p$, supplier with inconsistent beliefs is free to want to sell 300 units for \$150.
Comment: @Giskard but OP is talking about the supply-demand model. In the first sentence OP says "according to supply and demand when there's an increase in supply, resulting in surplus, the price falls till it reaches equilibrium". So as far as I see it OP is asking for an answer within a standard supply and demand model. Sure, what you describe can happen in a richer set of the models, but as I read the Q, OP is not discussing behavioral econ
Comment: OP is indeed trying to understand how agents' behavior works in standard D & P model. "*I produce 300 widgets to sell them at 150 dollars each*" is about the intentions/incentives of agents, why they should not do this.
Comment: @Giskard right but then once you have any model there will be some parameters inconsistent with the model, that is my whole point. As I understand it OP is perplexed why at the "equilibrium" price there is surplus supply on the market, well answer to that is that it's not an equilibrium. In any case there might be more than one reading of OP's question, I wanted to address this because I think that was the root cause of OP being confused
Answer:
What do I do with the remaining supply?
If, at this price (\$100) the supply is still greater than the demand, you could sell more units by further decreasing the price. This would nicely answer your question of "How does price decrease when supply increases?"

Some remarks:
"when supply increases" is quite multifaceted. In this context it would probably mean that the supply curve has tilted/shifted downward due to a new entrant/technological improvement.
The perfect competition model assumes agents without market power; that is, each firm is so small ("atomic") that were they to price above the market price none of their goods would be bought, and they have no effect on the market price.
Thus, a more accurate statement, is that within the perfect competition model, if the supply curve shifts/tilts so that supply increases, the new equilibrium price will be lower than the old one (if demand is strictly decreasing in price).


Why does reputation only carry over to meta?

Question: I noticed something weird for the way reputation works across the different stack overflow networks. For stack overflow meta, the reputation carries over from the main stack overflow site. But for other networks; for example, sports; the reputation is separate apart from the starting 100 bonus for being trusted on another network. If you can't actually gain/lose reputation on meta itself, why does it even have reputation? Or why isn't it done like all the other networks?
Comment: @psubsee2003 yes
Comment: So to clarify, you are wondering why meta sites inherit rep from their parent site, but completely different sites only provide the 100 point bonus for being a trusted user?
Answer: So you are really asking 2 separate questions.
1. Why do you have the same reputation on Meta sites as the main site.
Meta sites are seen as a semi-open site to help users ask questions and learn about how the main site works (provided they have 5 rep, or want to ask about their own question).  Reputation is a measure of trust that the community has in you.  So it makes completed sense that your main site rep be reflected in your meta rep.  You are the expert community on your site.  You don't want people from Gardening.SE or Bicycles.SE  telling people how Stack Overflow should work.  Likewise, you don't want people who have meta rep without earning it on the main site telling you what you should be doing.
The "community" of the main site is exactly the same as the "community" of the associated meta site.  They aren't 2 separate sites, there are more like 2 parts of the same whole. The community of the meta site must be the community of the main site, otherwise you have a bunch of people with no experience on your site telling you how to make it work.
Every site has its own rules and its own idiosyncrasies.  So only someone who is an expert in a specific site should be telling you only about that specific site.  An expert only in a separate site can't tell you with any authority why Stack Overflow works the way it does (like I said before, you don't want a Gardening.SE user telling you why your SO question was closed).  So that user shouldn't have any privileges on MSO unless they earned them on SO.
If you are looking for a global meta (covering all sites, not just Stack Overflow), you should be looking for Meta.StackExchange, but that is for global questions only.  Questions about a specific site should be asked on that community's meta.
2. Why do I get bonus reputation on new sites I join when I have enough reputation on another site
What you are seeing here is called the association bonus. The idea here is that you are considered experienced enough in how Stack Exchange sites work to be granted the minimum privileges on every site.  You basically have enough rep to comment, flag, upvote, and remove the basic "new user" restrictions, but you don't have enough rep to downvote or do anything else that requires a basic level of understanding in the specific community.
Comment: @CaryShindell absolutely not.  Every site has its own rules and its own idiosyncrasies.  So only someone who is an expert in a specific site should be telling you about that specific site.  If you are looking for a global meta (covering all sites, not just Stack Overflow), you should be looking for [Meta.StackExchange](https://meta.stackexchange.com/)
Comment: Thanks. I understand the reasoning for the second part. For the first part, I'm wondering why they don't have meta rep as the sum of rep on all networks? Because meta is supposed to apply to all of them right?


Cognitive (neuro)science and related mailing lists

Question: I am looking for cognitive neuroscience (and related) mailing lists. For some time I have been subscribed to Visionlist and found it to be a tremendous source of information about conferences, PhD and postdoc opportunities.
Does anybody else know any similar, good sources?
Thanks!
Answer: The Visionlist is indeed extremely helpful. It's not quite the same, but I found the mailing lists of the Organization for Human Brain Mapping (OHBM) and of the Cognitive Neuroscience Society (CNS) quite useful.
Answer: There is a recently created cognitive science mailing list that is managed by the Cognitive Science Society.
Information here: http://www.cognitivesciencesociety.org/2016/08/10/new-cogsci-mailing-list/
Subscribe here: http://lists.cognitivesciencesociety.org/listinfo.cgi/announcements-cognitivesciencesociety.org


Java Minecraft Structure Block transfer to a paid server my friend has

Question: i have my Structure Block all ready to go and found the file (took awhile ) and now im trying to figure out how to get the file into a hosted sever my friend has
Answer: You should put it in a corresponding folder in the world save folder of the server. Normally, the server's subfolder world corresponds to the folder with world name in .minecraft/saves although the folder name can be changed in server properties
For example, my experimental world is called 1_15_redstone, and the structure I saved was called inot. So, I take the file:
.minecraft\saves\1_15_redstone\generated\minecraft\structures\inot.nbt
and upload it to the server, placing it in the server's subdirectory
world\generated\minecraft\structures\inot.nbt
It's entirely possible the subfolder generated and its subfolders won't exist on the server - they are only created as a first structure block's structure is saved, so either create them, or just create and save any dummy structure in game on the server.


Utility to show file access statistics? (Windows)

Question: Is there a utility out there which which keep a log of which files are accessed during the day, and show a report of which files/folders where accessed the most?
Update:
Thanks for the answers - I'll look into them.  Just wanted to add a bit of context:  I'm looking at this really from a performance point of view - I want to know during the average day, which files/folders are causing the most IO work.
Answer: Check Process Monitor from Sysinternals.
It can be configured with various filters.
Begin with the following filter configuration,

Menu: Filter, Filter...
      Add: Operation is ReadFile
      Add: Operation is WriteFile

Try to fine tune the filter to your exact requirements, that way it will be less of a load on the system.
Comment: Strange, I don't have the options for ReadFile or WriteFile. I have FASTIO_READ though.
Answer: Alternatively, you could use the built in Audit feature. Right click on any folder or file, select properties/security/Advanced/Auditing. Add who you wish to audit against, everyone for example. Choose what you wish to audit for and away you go.
The information is collected and available in the Security Log in Event viewer. Here you can create custom views for the information you are interested in.  It can also be exported in a variety of formats for further manipulation.


How do I install a Realtek Wireless-N USB Adapter on my Linux OS laptop

Question: I just bought a Realtek wireless-n usb adapter and I'm having problems installing it to my Linux OS laptop. It will not run the setup.exe. It is a Ultra-Mini USB Wireless Lan 802.11N Adapter - 1T1R and I bought it at monoprice.com. Where can I go to and download the proper driver?
Comment: Welcome to Ask Ubuntu! Note that Ubuntu doesn't run .exe files (well any Linux OS for that matter!). .exe files run only on Windows OS. So this means you are trying to install a driver, that is meant for Windows OS instead of the one for Linux,  for your wireless adapter. So find a Linux driver for your wireless adapter and it should work fine.
Comment: Also from the next time you ask a question please remember to mention which version of Ubuntu you are using.
Comment: We can't answer this without your exact realtek model. What is the output of `lspci -nn | grep Network`? Please [edit] it into your question. Thanks!
Comment: It's a USB model, not a PCI one. I filtered the non-USB ones in my answer.
Comment: @pilona Ah, you're right! I missed that in the title. I guess it isn't unclear then :)
Answer: You likely don't need to install anything. The drivers for many of the Realtek wireless adapters are already in-tree. I have an 8192CU myself.
At least the following RT chipsets are supported:

8192CU
8188CU
8712
8188EU
8821 (USB?)

As for ancially matters:

It's NOT "Linux OS", just Linux to be generic, or Ubuntu.
You can't run Windows PE executables (.exe) under Linux. They're different. Linux uses ELF , and regardless the libraries seutp.exe is linked against are neither present nor of the appropriate format. You could use Wine to try and run the program but that is obviously futile here. This is a different OS.
Vendor-provided drivers are often outdated. In Linux, be wary of anything not in-tree, save a few.
If the vendor provided additional userspace to manage your wireless device, it's just reinventing and reimplementing the wheel. There's already a plethora of generic better-developed Linux-target programs for managing wireless adapters.


Remove and re-insert female threaded insert?

Question: I have a metal rod with these threaded female connectors on each side. I'm hoping to cut the rod down a bit to shorten it but still keep the female connector on the side i cut. Is there a way to remove and reinsert this? I'm not sure how it's attached - I got it off amazon as a camera arm.
Comment: thread a bolt into the insert ... gently tap the bolt with a hammer ... it is possible that the insert will get pushed into the tube ... if it does, then push it into the tube as far as the bolt allows and cut off the extra tube length ... repeat until the tube is the desired length
Comment: Probably just need to cut tube to length you want.  Tread section is probably bonded to tube at/near ends for only an inch or two.  Tube might be quite on weak/flimsy side towards centre(almost like a piece of thin tin).
Comment: If you look straight down that hole, is there a fastener or socket at the bottom? I assume not, but just checking. If not, I expect you will have to use destructive means to get it out.
Answer: Cut the rod to the desired length. Then get a rotary tool like a Dremel with a cutoff disk. Cut the tubing that holds the insert lengthwise down to the surface of the insert. Make three or four cuts. Then pry the tubing apart with a slotted screwdriver, freeing up the insert. Slightly chamfer the inside edge of the shortened length of tubing and tap/pound the insert into the tubing.
Answer: A bit of lateral thinking:

Leave the factory inserts at the end of the tube alone.
Cut a section out of the center of the tube.
Purchase a set of matching threaded inserts and a short length of all-thread with matching threads.
Insert a threaded insert into each of the newly cut ends, holding them in place with epoxy.
Screw together to make a shorter tube of the desired length.

Add epoxy to the threaded rod for a (mostly) permanent installation.
Leave loose for a tube that can pack down into an even smaller space for travel.
Comment: How about cut a section out of the center, then smear a metal rod with 5 minute epoxy and jam it into the open cut end of either side.  Push the cut sides together over the rod.  Wipe off extra epoxy.
Comment: That would also work, @Willk, for a permanently shorted and not disassemblable pole.
Answer: If you are willing to risk destruction of the item, heat may serve the purpose. As you wish to shorten the tubing, cutting off the threaded portion will prevent the remaining desired length from being damaged.
It's possible the insert is secured with what is often called Loctite™ and more generically called anerobic thread adhesive. The red version is nearly impenetrable once cured; only heat can break it loose. Secure the insert with a suitable bolt secured in a suitably immovable vise or similar. Consider to also add a locking jam nut on the securing bolt; see below.
Applying heat with a heat gun is probably more controllable than using a flame-based heat source. According to the Loctite™ web page, 500 °F / 260 °C is the release temperature. While heating, consider to twist and pull on the short section of tubing which you left in place for this purpose. You could also, prior to heating, drill a pair of holes perpendicular to the axis, beyond the insert, providing for easier twisting and pulling.
Once removed, thorough cleaning is indicated, as you'll want to use red thread locking adhesive for the replacement. You should have noted the approximate temperature at which the paint started to blister and consider that when heating the remaining tubing into which the insert is to be, well, uh, inserted. Place the insert in a freezer until frozen, or use dry ice for even lower temperatures. I don't know how red thread locker will handle the dry ice temperatures. Loctite's ™ web site says cold temperatures will slow curing time, but does not indicate any problems related to low temperature. I would not be surprised if the liquid freezes on contact with metals at dry ice temperatures.
This may be overkill, if the insert is not held by adhesive means. If thermal methods were used, the same method could be used to replace it.
Check also that mechanical crimping is not in evidence. If so, rotary grinding tools are indicated, aka Dremel™.
You already know the insert fits, so it should not take much convincing.
Comment: Think the OP only needs to cut out a section of centre of tube length.  Inserts probably only at ends.  Problem of over thinking a problem.
Comment: @Willk  it depends on what the OP wants exactly.  Two short tubes with one threaded end or two short tubes with both ends threaded.  Both ends threaded will probably require buying two threaded inserts to add to tubes.  My thinking is those inserts are only an inch or two in length in cheaper tube.  OP might want/need to add solid rod for strength to other end.
Comment: @Crip659 - I was going to post exactly that but now people will think I am copying you because I will be.  How about you put that as an answer along with how to join the 2 ends of the rod back in the middle.  I have an idea about that but am going to post it as a comment if you have a different idea.


How can I read the Beta value of a BJT for a specific circuit from the datasheet?

Question: How can I read the Beta value of a BJT for a specific circuit from the datasheet?
I tried to find currents first in order to find the Beta value but eventually I couldn't because I didn't had the Beta value. I couldn't make sense of the datasheet.
Comment: I didn't understand. I am provided with these two, data sheet and circuit. "Choose
Beta
from
the
given datasheet "
Comment: the datasheet is reminding you, politely, that the specification for beta (also called h_fe)  is a very inconsistently controlled value, just like the other commenters are saying. There are other parameters of transistors that are more reliable, but they are not quite as easy to compute.
Answer: Setup
Let's examine your case on the left and, on the right, the usual one seen over and over again:

simulate this circuit – Schematic created using CircuitLab
Note that I've drawn an equivalent schematic for CASE 2. The equivalent on the right side of CASE 2 looks a lot like CASE 1. But the key difference is that we can set two values, \$V_\text{TH}\$ and \$R_\text{TH}\$, for the CASE 2 where we can only set one, \$R_\text{B}\$, for CASE 1. So CASE 2 has two degrees of design freedom against only one degree for CASE 1. There are more differences as we will soon see.
I've also decided on a quiescent collector current of \$I_{\text{C}_\text{Q}}=3\:\text{mA}\$, as shown. Assuming \$I_{\text{E}_\text{Q}}\approx I_{\text{C}_\text{Q}}\$, the collector and emitter voltages can be worked out, also as shown. And assuming \$V_\text{BE}\approx 700\:\text{V}\$ then the base voltage also falls out, easily.
I didn't select the collector and resistor values. I just took the values you show in your question. They probably aren't very practical. But they are good enough to get a point across.
Case 1
Here, you need to find \$R_\text{B}=\beta\cdot \frac{20\:\text{V}-7.3\:\text{V}}{3\:\text{mA}}\$. But you don't know the value of \$\beta\$. And it varies a lot between BJTs; even ones from the same designation and manufacturer. It also varies over temperature and it varies when the collector current varies.
Let's just say a BJT is measured with the resulting value of \$\beta=150\$. We can now work out that \$R_\text{B}=150\cdot \frac{20\:\text{V}-7.3\:\text{V}}{3\:\text{mA}}=635\:\text{k}\Omega\$.
Using that exact resistor value we find that all the numbers work out. The base, collector, and emitter voltages are on the mark.
Case 2
Here, the situation is slightly more complex. Two resistor values need to be found, \$R_1\$ and \$R_2\$.
The usual rule applied for biasing this case is to use what's called a stiff divider pair. This means that about \$10\times\$ the needed base current should be traveling through the two resistors, quiescently. Knowing the measured value of \$\beta=150\$, find \$I_\text{B}=\frac{3\:\text{mA}}{\beta=150}=20\:\mu\text{A}\$. So this means about \$200\:\mu\text{A}\$ quiescent current in \$R_1\$ and \$R_2\$.
One note to be concerned about here is that \$R_1\$ must also carry the base current, along with this quiescent current. So \$I_{R_1}=200\:\mu\text{A}+20\:\mu\text{A}=220\:\mu\text{A}\$ and \$I_{R_2}=200\:\mu\text{A}\$. Now compute the value for \$R_1=\frac{20\:\text{V}-7.3\:\text{V}}{220\:\mu\text{A}}\approx 57.73\:\text{k}\Omega\$ and \$R_2=\frac{7.3\:\text{V}}{200\:\mu\text{A}}= 36.5\:\text{k}\Omega\$.
Then find \$R_\text{TH}\approx 22.36\:\text{k}\Omega\$ and \$V_\text{TH}\approx 7.747\:\text{V}\$. Just to verify the base voltage in this case, compute \$V_\text{TH}-I_\text{B}\cdot R_\text{TH}=7.747\:\text{V}-20\:\mu\text{A}\cdot 22.36\:\text{k}\Omega\approx 7.3\:\text{V}\$, which is exactly the design goal.
Using those exact resistor values we find that all the numbers work out. The base, collector, and emitter voltages are on the mark.
Sensitivity of \$I_\text{C}\$ with respect to \$\beta\$ -- analyzing both cases
The important question to ask now is this: "If we designed a circuit assuming a specific value for \$\beta\$, how much would different values for the actual \$\beta\$ found for various BJTs upset the quiescent collector current?" We know that changes in the quiescent collector current will impact the collector and emitter voltages for the circuit and, consequently, also the base voltage, too. So the hope is that a circuit with specified part values for the resistors is sufficiently stable and won't be too upset if one BJT's \$\beta\$ is different than another's.
One way to look at this question is to define \$\beta\$ variations as a percentage. So, let's say that while we did measure one BJT with \$\beta=150\$, when measuring more of them we find \$110 \le \beta\le 200\$. A span of almost two-fold. Roughly, let's say this means we can expect about \$\pm 35\%\$ variation in \$\beta\$. What %-change might this mean for the designed quiescent collector current?
For CASE 1 the quiescent collector current is:
$$I_\text{C}=\beta\cdot\frac{V_\text{CC}-V_\text{BE}}{R_\text{B}+R_\text{E}\cdot\left(\beta+1\right)}$$
For CASE 2 the quiescent collector current is expressed similarly, as:
$$I_\text{C}=\beta\cdot\frac{V_\text{TH}-V_\text{BE}}{R_\text{TH}+R_\text{E}\cdot\left(\beta+1\right)}$$
The sensitivity equation is \$S^{I_\text{C}}_{\beta}=\frac{\frac{\text{d}\,I_\text{C}}{I_\text{C}}}{\frac{\text{d}\,\beta}{\beta}}\$ and once this value is computed, it can be used this way: \$\%\,I_\text{C}=S^{I_\text{C}}_{\beta}\cdot \%\,\beta\$.
I won't belabor the calculation details here. But for CASE 1 find:
$$\begin{align*}
S^{I_\text{C}}_{\beta}=\frac1{1+\beta\cdot\frac{R_\text{E}}{R_\text{E}+R_\text{B}}}
\end{align*}$$
Using the above equation and substituting in values for your (left side) design, find that a \$\pm 35\%\$ in \$\beta\$ suggests on the order of about \$\pm 23\%\$ variation in the collector current.
Now, for CASE 2 find:
$$\begin{align*}
S^{I_\text{C}}_{\beta}=1-\frac{\beta}{\beta+1+\frac{R_\text{TH}}{R_\text{E}}}
\end{align*}$$
Using the above equation and substituting in values for the right side design, find that a \$\pm 35\%\$ in \$\beta\$ suggests on the order of about \$\pm 2.4\%\$ variation in the collector current.
CASE 2 appears to be about \$10\times\$ more stable than CASE 1 with respect to \$\beta\$ variations. So, we should prefer CASE 2 to CASE 1.
The price paid is the added \$200\:\mu\text{A}\$ current through \$R_1\$ and \$R_2\$ and the associated manufacturing costs related to adding another resistor. But the benefit may be worth having, too.
It's possible to relax the stiffness of the divider pair. Using \$100\:\mu\text{A}\$ instead of \$200\:\mu\text{A}\$ for the biasing divider pair, a \$\pm 35\%\$ in \$\beta\$ then suggests on the order of about \$\pm 4.2\%\$ variation in the collector current. Again, still pretty good and a lot better than without the divider pair in the circuit.
Further considerations may include an additional resistor and capacitor that is used in a bootstrapped design. Here, the biasing resistor divider pair's loading on the input signal is greatly reduced and it's possible to consider further trade-offs for the biasing resistor divider pair's quiescent current. The point in mentioning this is tell you that your imagination should not be hindered, but instead freed up to think about and try novel ideas you may wonder about. Don't get stuck in the mud by what others tell you is true. Think for yourself. Create ideas and test them. (Most will die on the vine, agreed. But once in a while you might come up with something useful, too.)
Summary
A truth should be arriving now, I think. Circuit designers using discrete BJTs usually choose circuit topologies that are less sensitive to BJT part variations, rather than more sensitive. This means that you don't need to go diving into datasheets to find some exact value for \$\beta\$ for your design. Instead, you'll design around the problem and make your circuit less sensitive to the issue. How much sensitivity you can accept is one of those choices you'll have to make, based upon many factors that will be somewhat different for each project goal.
Making a circuit less sensitive to \$\beta\$ variations is an example of what it means to place a design into better management. The better your circuit design keeps control over important design conditions when part parameters vary (as they will), the more the circuit manages the situation.
A small, additional point should also arrive now. It is possible to estimate the sensitivity of a circuit to certain parameters. There are methods you should learn to use well that, if you find it worth the effort at the time, can help you place boundaries around circuit variations you care about. It is just one more thing to learn. But a worthwhile thing.
Answer: You don't. You get a vaguely representative value from the datasheet, and design the biasing circuit and overall performance to be relatively independent of the actual value.
Then, when Beta turns out to be 3x the datasheet value for the transistors you have in your hand, you are pleasantly surprised instead of disappointed.
And yes, 3:1 is a realistic spread of values.
(This just explains why, I'll not attempt to compete with @jonk's excellent worked example showing how)
Answer: There's a reason people don't like that kind of biasing.
Choose a beta somewhere in the middle -- say 50.
Solve the circuit for the collector current.
Now choose the beta that goes with that collector current.  Go back to solving for the collector current, choose new beta, etc..  You should settle out to a value of collector current (and beta) pretty quickly.
Comment: I have first assumed the Beta 50, then 100. And it seems that I shall settle on 70.
Answer: Image from datasheet of 2N3904

Your image of datasheet states minimum guaranteed value and typical.
Comment: I still didn't understand how can I use this information to use. Perhaps lets say I want to calculate the currents this circuit. For the Beta value do I use the minimum values? And which is 30?
Comment: @CanberkÖzçelik Actually, you can't use the graph for your circuit. The graph shows **typical** values and is intended to show you how the current gain varies with collector current. The actual gain value for any given transistor may be much different from this typical value.


Can I travel to Paris for a day with a single entry visa for Schengen from Switzerland?

Question: I am visiting a friend in Switzerland for ten days. I have already got visitor's visa for the same on my Indian passport. Particulars mentioned on my visa are:  1. 'Etats Schengen' , 2. Single entry 3. Dates of visit. & 4. Type of visa : C.  I understand that having already got 'Etats Schengen' visa, I can travel to all Schengen countries.
I am also planning to visit Paris for a day during my stay in Switzerland. However, I never mentioned this in my visa application. I am planning to take a train from Geneva to Paris and book a hotel in Paris for one night. Can I possibly plan my Paris trip this way as I have Schengen visa, or I am not allowed to travel out of Switzerland as I never mentioned this in my visa application?
Also what does Single entry on my Schengen visa means: does it mean that I can enter and leave Switzerland only once or it means that I can enter and leave the Schengen region only once.
Comment: Once you have a Schengen visa, you can travel through all Schengen countries as you wish. Single entry refers to the fact that you can enter and leave the Schengen region only once.
Answer: Switzerland and France are both part of the Schengen area. Since you do not exit the Schengen area when you travel from Switzerland to France, you won't have to re-enter, thus all will be fine.
Single-entry means that you can only enter and exit the Schengen area once, in other words, every trip to the Schengen area needs its own visa.
Answer: I added my comment as an answer, since it is more an answer than a comment :)

Once you have a Schengen visa, you can travel through all Schengen
  countries as you wish. Single entry refers to the fact that you can
  enter and leave the Schengen region only once.
Answer: Answering for the generic case...
There are 650 different ways to arrive/visit/depart two countries in the Schengen zone.  This number doubles when single-entry and multiple-entry visas are considered.
France-Germany, Germany-France, France-Italy, Italy-Germany, France-Spain, Italy-Spain, and so on. There are too many of these to deal with on a case-by-case basis.
When three different countries are considered, the number of permutations is more than 15,000!
Regardless of which combination/permutation is selected, the same rule applies... Once you have arrived at a Schengen member and cleared immigration control, there are open borders to 25 other countries.  You can visit them or catch a flight home from them.
This answer holds true for all Schengen short-stay visas except those with a specific territorial limitation specified on the face of the visa.
Answer: Single entry means you are allowed to cross an external border between a non-Schengen country and a Schengen country once (i.e. it refers to the Schengen area as a whole). You don't need a multiple-entry visa to travel through several countries within the area.
I have recently seen more frequent passport checks for trains to France starting in Geneva but the police was only looking at the ID page, not at visas.


Looking for open source Spatial file server that ArcGIS 10.1 will connect and work with?

Question: I'm looking for an open source spatial file server to house and serve my GIS data.  I'm currently using my Ubuntu Server as a ssh file server and have to download the data to the local computer, manipulate and then re-upload to the server.  I would prefer to use ArcCatalog to connect to the server and manipulate the data in-situ.  Are there any open source Spatial servers that Arc will communicate with? I'm not very interested in WMS or other web based displays.
Comment: The answer is likely postgis on postgresql
Comment: postgis - see it in action http://www.youtube.com/watch?v=gsMEwdwH6Ts
Comment: It sounds like @Mender is looking for a simple file server or network share that can be connected to from ArcCatalog.  It doesn't seem like a database server will suit their needs.
Comment: When you say spatial server, do you mean something like GeoServer or MapServer? Or do you mean a spatial database like PostgreSQL or MySQL?
Comment: MapServer and GeoServer appear to be web publishing servers? I'm not looking to publish spatial data to the web, but simply connect to a file server through ArcCatalog and create, manipulate, and process, raster and vector data, in  geo-databases and shapefiles.  Ideally, I would like to move away from Arc, but it will take some time...
Answer: For my own work, I use a Postgres server with PostGIS extensions.  I personally like it because of the new RASTER support that was built into PostGIS v2.
Here are some resources that might help you:
http://postgis.net
http://www.postgis.us (The book "PostGIS in Action" is excellent)
http://linfiniti.com/2012/05/installing-postgis-2-0-on-ubuntu/
http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//002p0000003r000000
Answer: If all you need is a file server, not a spatial database server, the simplest way is to just install samba, share a directory via /etc/samba/smb.conf (or use a gui if you don't need anything complicated like active directory integration) and map that directory as a network drive in Windows Explorer.
Comment: Sure sounds like all he wants is to share files, so this really hits the mark. +1 from me.


Can I create/update a list item by uploading a document to a document library in SP2010?

Question: I am looking for a way to capture data from a formatted word document users are currently using. Rather than create a list where the users input the information and it generates the document in the document library is there a way to reverse the process? Where a user uploads the document already filled out and the system "pulls" the information into a list? This would help with retrieving historical data.
Answer: I'm not sure how it would work with a word document, but maybe you can look into using Microsoft Infopath forms? The forms use XML data which can be promoted into list columns. So users can fill out the published infopath template, and the resulting data can populated into the form library.
Answer: You can use Word Quick Parts and properties promotion:

Create a document library.
Add fields you want.
Create a new Word document from the "New" button in the ribbon.
Design in it the form as you wish.
Place QuickPart (from the "Insert" ribbon of Word) to place doc lib fields wherever you want.
Save the document back to the SharePoint document library.
Download the file locally.
Go to the doc lib settings, Advanced Settings: allow management of content types.
Go to the doc lib settings, click on the "Document" content type from the new Content Types section.
Go to its advanced settings and upload the file from step #7 as a new template for the content type.
Now, whenever a user creates a new document from the "New" button of the ribbon in the doc lib, Word will open on the Template you prepared. The user can edit the QuickPart and save the document to SharePoint. When it's saved, proprerties will be promoted to actual doc lib's columns.

A good tutorial about this approach (with slight differences with my procedure above) can be found here.
Answer: I would try to write an event receiver on ItemAdded and ItemUpdated to read out the contents of your documents and write the details into the fields.


Calculating Points Per Polygon

Question: If I have a map of the U.S. with individual polygons at the county-level, and then in another layer, a set of points of interest, is there a way to tabulate how many POI per each polygon ("county") and export that data? I'd like to create a histogram showing how many POI per county there are for all counties.
Comment: Welcome to gis.stackexchange! Please note that a good question on this site is expected to show some degree of research on your part, i.e. what you have tried and - if applicable - code so far. For more info, you can check our [faq].
Answer: You should do a spatial join and join the polygon id to the points. Right click on the point layer in your table of contents and select join.  Make sure its a spatial join and you joining Polygons to Points, also make sure each point gets the attributes of the polygon it is in (not nearest too)

Once this is done you will have a new featureclass that holds your points with an attribute showing which polygon it is in.  You will then use Summarize (right click on the field you want summarized in the attribute table and summarize on the field that holds the polygon ID.  This will give you a total count of points in the poly.
Answer: You can use a tool that calculates the count of points inside polygon, even using a buffer. e.g. Using this tool you can count the number of points that fall inside the polygon itself and 300m buffer. If you want to calculate just the polygon and no buffer then set search radius to 0m.

Details of the tool can be found here.
Usage: Just locate the tool in the arc catalog and use.
Tool download link
N.B. You are welcome to suggest on this tool. I will try to incorporate your suggestions.
Answer: There are some methods to do it. If your poi's do not have a unique ID to join the Counties then :
You can use spatial join .The target feature is POI's and the join features is counties. The result of spatial join is POI features that have attributes of counties. Then use summary statistics on join result and  summarize your data based of desired fields.

Calculating Points Per Polygon


$\mathbb{C}P^n$-bundle over $BU(n)$

Question: The inclusion $U(1)\times U(n-1)\to U(n)$ induces a map $BU(1)\times BU(n-1)\to BU(n)$. This source claims that the fiber of this map is $\mathbb{C}P^n$. Could someone please explain why this is true?
Answer: There is a typo --- it should be $\mathbb{C}P^{n-1}$ (as you can also see from the cohomology ring in the next sentence).
$BU(1)\times BU(n-1)\to BU(n)$ is the classifying map for taking orthogonal direct sum of a rank-$1$ bundle and a rank-$(n-1)$ bundle.  So the fibers are ways to split an $n$-dimensional vector space into the sum of $1$- and $(n-1)$-dimensional subspaces, but that is just choosing $1$-dimensional subspaces from a fixed $n$-dimensionsional one (the $n-1$ must then be its orthogonal complement), which is $\mathbb{C}P^{n-1}$.
Comment: Ah, got it. Thanks.
Comment: A follow up question: how do we know Leray-Hirsch applies here? i.e. Why is the generator of the cohomology of $\mathbb{C}P^{n−1}$ the pullback of some element of the cohomology of $BU(1)×BU(n−1)$?

$\mathbb{C}P^n$-bundle over $BU(n)$


Can design like this be created in Affinity Designer or Photo?

Question: How can such design as below be created with Affinity Designer/Photo or it's a 3D design? I also can't understand how the layering works in here. Are those rectangles of different colour and luminescence and they together are looking like that? Or there is a light source behind the rectangles?
Comment: Hi. I don't see why you couldn't use something like Affinity Photo. Most raster image editors I think would be capable of this. Perhaps semi transparent filled shapes simply stacked as layers, and a layer on top with blending mode set to colour burn, so that it colours the layers underneath. You may have to experiment a bit though.
Answer: I didn't find I needed a tool I couldn't find in Affinity... no need for an illustrator-style blend tool - this was my result.

First I created a simple rectangular path, gave this a gradient (added noise to the colours at both endstops)

Second, I then gave it a transparency gradient (with the transparency gradient tool).

Then I opened the Appearance palette, duplicated that fill, switched the blend mode of the first fill layer to Screen, the second one to Hard Light.

Then I duplicated, moved slightly and scaled vertically, then I used (Cntrl-J) to repeat this to get my overall composition.
Finally I selected each poly in turn and assigned an object-level transparency to complete the effect.

Then I added an HSL adjustment layer at the to of the layer stack (Note 1: I could have targeted individual shapes by dragging the adjustment layer onto them, but this was simpler for now) and set a mask for the layer, which I then added a white to black linear gradient into... to give a gradiated desaturation and subtle colour shift towards the blue-green.

And so my last final version looks like this:

Which I think pretty well covers the original question's example.
Note 1:
I in fact tried the HSL adjustment per shape layer just to see how much the added control aided a better final result - it did, and allowed me to produce a more discrete-per-sheet desaturating effect, but it was a bit unwieldy and the final results not enough different to make it worth it!
Answer: At least nobody will say "get Blender or some other 3D program which can make photorealistic renderings, draw some equally sized parallel glass rectangles and insert to them colored internal gloss, set up a short focal length rendering camera for strong perspective."
That's because the image presents something which is impossible in 3D space - at least as a stack of equally sized rectangles. The red glasses are nearest the camera for the internal gloss visibility, but for the geometric perspective they should be the farthest items.
As a 2D drawing it's possible (as you have shown). Affinity Photo and Designer should both be flexible enough for this. Place one distorted transparent rectangle per a layer (with edge internal glow effect and painted light), but let the geometrically most distant glass be the top layer. The bottom layer contains the  geometrically nearest glass.
In the next image there's a 3 layer example of the layering idea. The geometrically most distant item with strong white-red fill is not at all obscured by the geometrically closer items because the layering order is inverse. No attempt to replicate exactly your colors.

Then there's some grain or noise effect, but I skip it.
Comment: Not that anybody would suggest Blender anyways, because this would be the wrong site for that.
Answer: This design requires shape blending. As far as I know that's not possible in your software. But you could blend the shape manually.
You would take two shapes like this and the interpolate some steps in-between.

Then set the opacity of all individual shapes to about 40%.

Add some inner shadow and texture and you got something quite similar.


Nonalcoholic Substitute for Marsala Wine

Question: For personal reasons I won't purchase alcohol or have it in my home, but I'm a bit of a foodie and love Chicken and Steak Marsala.  I've found decent nonalcoholic substitutes for dry and sweet white wines and burgundy (Meiers Sparkling Juice), which covers most of the recipes I've wanted to make, but I've never found a good substitute for Marsala.  Are there any non-alcoholic versions that would pass in a recipe, or a decent mix of other juices or ingredients that would pass, even if I have to process it somehow?
Comment: Yes, I'm well aware of the effect that cooking has on alcohol, but as I said, *for personal reasons, I won't purchase alcohol or have it in my home*.
Comment: related : http://cooking.stackexchange.com/q/1332/67
Comment: alcohol is very volatile and so quickly evaporates at cooking temperatures
Answer: I have cooked quite a few times for Islamic guests and finding non alcoholic substitutes for wine is never easy. In general you find a lot of solutions floating around on the Internet based on grape juices, but I have never been quite satisfied with the results that brings me.
My best results have been achieved through using non alcoholic wine instead of grape juice. Especially the brands of non alcoholic wine that are produced by chemically extracting the alcohol from the finished product come quite close to behaving like regular wine in sauce recipes.
Since you are from the US you might want to check out these guys: Ariel
Specifically for Marsala I have found some recipes calling for the following substitutes:
¼ cup white grape juice
2 tablespoons sherry vinegar
1-tablespoon nonalcoholic vanilla extract
As said, I would replace the grape juice in this recipe with non alcoholic wine for the optimal result.
Comment: The brands I used did not. They were imported by a friend of mine. I even discussed their use with the Imam of our local mosque. Good point to be vigilant on this though, thanks!
Comment: Non-alcoholic wines (including dealcoholized wines) usually still contain a portion of alcohol. Many Muslims will still avoid such products.
Answer: It's very difficult to replace Marsala - it has plenty of flavors.
There is a fair chance that you like a specific flavor within the Marsala, which is the important distinction you desire.
The flavors of Marsala are often describes as walnut, curry plant (Helichrysum italicum - not to be confused with curry leaves), chocolate, leather, honey and dates, together with a distinct acidity and saltiness.
So, if you want to recreate the flavor, you have to experiment with these flavors, instead of "doing something with grapes". The most difficult part of course is leather.
I would try long-brewed green tea, which will end up with a lot of tannin - this is the bitterness and astringency you need. Together with dark chocolate, honey, salt and wine vinegar for the acidity, you could, in theory, create something similar.
If you want to cheat, you can just get Marsala flavoring, f.e.:
http://www.bickfordflavors.com/products/marsala-flavor
Comment: That particular flavoring isn't great for this application.  I've come much closer with a mix of natural ingredients I'm still working on.
Answer: You may be able to mix a sugar syrup with balsamic vinegar to get a similar effect.
You can take white sugar and mix it with as little boiling water as possible to make it all dissolve, and then add a bit of Balsamic. I'm not sure of exact quantities, but you can add a bit, taste, and then correct as needed.
It isn't a perfect substitute, but should work well for a cooked dish.
Answer: I tasted the marsala I just put in my stew, and to me it tasted like watered-down prune juice. If I was going to substitute it, I'd use 1/4 cup prune juice and 3/4 cup water. It'd be a site cheaper, too. I just paid $12 for something that tastes like watery prune juice.


Can the Canon EF-M film SLR use the focus by wire lenses?

Question: The old Canon film camera EF-M, not to be confused with mirrorless cameras featuring an "EF-M" lens mount, did not have auto focus ability and was manual focus only. Does it support the focus by wire lenses in the EOS line? Does it even have any electrical connectors in the mount (apart from the ones controlling the aperture blades)?
Comment: It probably has electrical contacts, as the EF lenses do not have aperture ring. I don't know if it works with focus by wire lenses, though.
Answer: I don't know about the focus-by-wire bit, but this photo.net discussion thread includes side-by-side images of the mounts of a 5D and an EF-M, and shows that the EF-M did indeed have all the electrical contacts of the EOS mount.
My guess would be that manually focusing with focus-by-wire will probably still work, since that's more about electronic communication between the lens's focus motor and the manual focus ring, not about lens-to-body AF communication, which the EF-M lacks.
Comment: @MichaelClark Your guess sounds better than mine. I assumed that if there was aperture control, then at least power was being fed to the lens, and that would be all that was required.  But if AF communication has to be established to turn on focus-by-wire, then it wouldn't work. Trouble is that the EF-M is rare and the focus-by-wire lenses are exotics, so it's unlikely we'll find an actual usage report.
Comment: Manual focus-by-wire only works when the shutter button is half pressed (or the AF-On back button), so there may need to be some exchange of information between the lens and camera for manual focus-by-wire to work. My gut instinct would be that one could not use manual focus-by-wire lenses with the EF-M, mainly because no such lenses existed in Canon's lineup when the EF-M was offered.
Comment: Well, except for the 200mm f/1.8 and the 1200mm f/5.6. So maybe it will provide for manually focusing focus-by-wire lenses.
Comment: With the newer STM lenses all being manual focus-by-wire someone with an EF-M may eventually try one on it and post the results.
Answer:
There are currently 2 types of Canon STM lenses: Fast and silent Lead-Screw Type STM and slow and noisy Gear-Type STM.

The Gear type STM lenses (40mm 2.8 STM and 50mm 1.8 STM) work fine in manual focus with the EF-M, but the Lead screw type lenses (10-18mm STM and 18-135mm STM) will  NOT manually focus.
(I also tried the new 18-135mm Nano USM and 70-300mm Nano USM II, and they both also do NOT manually focus on the EF-M)
SO, the EF-M works just fine with the 40mm 2.8 STM and 50mm 1.8 STM lenses, but just as with a DSLR, you do need to half press the shutter to get the metering started before the electronic STM focus will work. It works with the lens set to either AF or MF.
Once it starts working, the AF or MF will continue to work indefinitely, as long as you keep turning the focus ring. This continues even after the cameras metering as stopped. If you stop focusing, the STM will lose power after about 4 seconds of idle time. A half-press tap of the shutter button brings it back to life again.
Image Stabilization is a different story as it does not appear to work at all.
I also tried using my old EF 35-80 Power Zoom lens on the EF-M, and the power zoom function DOES work. But, because this lens has no manual focus ring, the lens of course is not really usable on the EF-M.


How do I make a slow clock without taking up space?

Question: I'm making a minigame where a player has to survive in essentially a world of hell. I am creating a "water bar", where players must drink to survive. It is a dummy scoreboard objective. I want to run the command
    "/scoreboard players @p remove water 1"
every 3 minutes so players can run out of water. The current loop I have is a circle loop (https://i.ytimg.com/vi/0c-NGRXY5u0/maxresdefault.jpg) but much bigger than the one shown. Is there a way I can make a loop that's much smaller than the one I have currently but still sends a signal to the command block once every 3 minutes?
Comment: **Don't use a redstone clock for triggering command blocks!**  This is beyond bad and into extremely evil territory.  You can make a long period clock with just a few command blocks and the scoreboard.  There are other options available as well, but for the love of god don't use a redstone clock.
Comment: @MBraedley Wow, that's a bit of an extreme reaction to a tiny bit of caused lag. Sure, avoiding redstone is good, but it's not that extremely important. And that comes from the person who's currently in the process of removing the [minecraft-redstone] tag from almost all [minecraft-commands] questions.
Comment: @FabianRöling It has nothing to do with lag, at least not directly.  Mixing redstone and command blocks is wrong in practically every situation.  Using a redstone clock, especially a long period redstone clock is the worst example of mixing redstone and command blocks.  That was just as true 2.5 years ago as it is today.  When you see someone doing something _this wrong_, you don't indulge them, you correct them immediately.
Answer: You'll have to work out the math a bit, but a non-command block slow clock I like to use basically uses an And Gate with two asynchronous loops of redstone, with a single tick pulse going in circles until they both hit the And Gate at the same time. For example a loop of 10 ticks and a loop of 11 ticks set off at the same time will not line up until 110 ticks. Normally 110 ticks of delay would be over 27 repeaters, but using the two loops only costs 6 repeaters. You can dramatically increase duration by using a third loop, however finding the correct tick counts involves a bit of math; using a spreadsheet like Excel helps a lot.
Edit: I just did the math in Excel, because I love math, Excel, and redstone haha. One (there can be other possible solutions this is merely the first one I found by randomly typing in numbers) solution is 49 and 75 tick loops, which is 13 and 19 repeaters. These will only line up after 3675 ticks, which at 20 ticks a second is 183.75 seconds or basically just slightly longer than 3 minutes.
For comparison to achieve that long of a delay with just repeaters on their own you would need 919 repeaters. 32 repeaters or 919 repeaters...a clear choice to me!
Comment: Sorry I already had an appropriate answer. ↓
Comment: Questions can have more than one answer. ;) Plus variety is the spice of life. Perhaps the concept won't be useful now but it might be later on. For example the minecart/cobweb method requires quite a lot of vertical space, while mine requires more horizontal space. Depending on the needs of the situation either could be viable! :)
Comment: ok i tried it with my new map and it worked better than I expected thanks!
Answer: You can make a slow clock quite easily with a minecart and cobwebs. Make a track that runs uphill and then falls onto cobwebs. For every cobweb you place, the minecart will take 30 more seconds to fall. Then, at the bottom, put powered rails and 1 detector rail to send out a signal, then connect that track to the one running uphill to make a loop.


Poor network performance from KVM virtual machine

Question: I am running a 32-bit Linux virtual machine on KVM. The host machine is a 64-bit Linux machine connected to a LAN.  Attempting to transfer files with scp from the KVM machine to a server on the LAN gives abysmal performance, about 500kB/s over gigabit Ethernet.  Around 1% of the expected rate.  Any suggestions?
Answer: Consider using virtio. It allows a direct connection between the VM and the host without the need to emulate (slow) hardware. I measured high network performance improvements with it.
For example, you can enable the virtio network device by the kvm command line parameter "-net nic,model=virtio".
If you are using the virtio block devices, please note that the new device names are then "vda1" etc., but this should be not a problem since current Linux distributions detect the partitions according to their UUIDs.
Comment: Wow!  Simply, wow!  Why is this not the default?  Note that specifying this option overrides the defaults, ``-net nic -net user``.  Remember to add ``-net user`` after the virtio option.
Comment: note for the future: virtio was default when I created the VM in virt-manager, but I had to change the MAC and for some reason, THAT defaults to `rtl` and not `virtio`. Maybe a bug?
Answer: It might be a problem of the Disk I/O performance inside the guest. If you are using a disk image, few steps apply to have better performance :
Firs, you will have to play around with the cache option of the disk configuration of your guest.

By default, writethrough caching is used for all block device.
  This means that the host page cache will be used to read and write
  data but write notification will be sent to the guest only when the
  data has been reported as written by the storage subsystem.
Writeback caching will report data writes as completed as soon as
  the data is present in the host page cache. This is safe as long
  as you trust your host. If your host crashes or loses power, then
  the guest may experience data corruption. When using the -snapshot
  option, writeback caching is used by default.
The host page can be avoided entirely with cache=none. This will
  attempt to do disk IO directly to the guests memory. QEMU may
  still perform an internal copy of the data.
Some block drivers perform badly with cache=writethrough, most
  notably, qcow2. If performance is more important than correctness,
  cache=writeback should be used with qcow2. By default, if no
  explicit caching is specified for a qcow2 disk image,
  cache=writeback will be used. For all other disk types,
  cache=writethrough is the default.

Then, you will also have to play around with elevator option of the kernel : you will have to append elevator=noop at your grub linux command line like this :
# Edit your /etc/default/grub.conf (on Debian-based distribution)
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash elevator=noop"

A better explaination of this is available at : http://lonesysadmin.net/2008/02/21/elevatornoop/ ; but in a few words, the host linux kernel and the guest linux kernel both try to optimize I/O and it tends to be worse than anything for the guest (the guest should leave this task to the host).


Why do we calculate variance if standard deviation serves the ends well?

Question: I don't understand why we even care for square units. How does it make sense that if you take the squared difference of each data set and mean, then divided it by $n-1$ gives us a measure of spread? Variance is not as intuitive to me as standard deviation, which makes absolute sense. Can anyone help me understand the importance of variance and how its formula makes sense?
Comment: How do you calculate standard deviation? I know a couple of ways to do it, but the last step is always taking a square root to get the final answer. Just before you take the square root you have a number which is called the variance. So if I take your headline literally, the answer to "why do we calculate variance" is that if you want standard deviation, you're going to get it by calculating the variance first.
Comment: One advantage of variance is that for sums of independent or uncorrelated random variables, you can sum the variances.
Comment: Is your problem with the scale of variance, or the fact that its formula (and that of standard deviation) has a squared term?
Comment: Have you ever in your entire life calculated the standard deviation of a set of data points? Have you ever in your entire life **seen** someone  calculate a standard deviation? Have you ever seen the formula for standard deviation? If the answer to any of those questions is "yes," I am astounded that you could make the comment you just did. It seems you need to do some studying; perhaps here: https://www.khanacademy.org/math/statistics-probability/summarizing-quantitative-data/variance-standard-deviation-population/a/calculating-standard-deviation-step-by-step
Answer: My opinion :
A naive approach for measuring the spread around the mean would be $\mathbb{E}[|X-\mathbb{E}[X]|]$, but absolute value have bad properties for different reasons and I guess thats why we prefer to use the square instead of absolute value. The square function is a smoother function and therefore have better properties for optimization etc..., which lead to $\mathbb{E}[(X-\mathbb{E}[X])^2]$. However due to square it will change the magnitude of the values involved and to rescale it we put a square root, leading to standard deviation.
Answer: Standard deviation is the square root of variance, so they're measuring the same thing. The standard deviation approximates a typical element's distance from the mean (as you pointed out), so it's useful for visually understanding a distribution, whereas the variance has more convenient algebraic properties and tends to show up directly in probability theorems more often. Luckily, it's easy to convert between the two.
Answer: A couple of reasons involving statistical practice.
(1)  For a random sample of size $n$ from a normal population where $\mu$ and $\sigma^2$ are both unknown, one has the relationship
$$\frac{(n-1)S^2}{\sigma^2}\sim\mathsf{Chisq}(\nu= n-1),$$
which can be used to make a CI for $\sigma^2$ and to test hypothesis involving $\sigma^2.$ [To find a CI for $\sigma,$ take square roots of endpoints of a CI for
$\sigma^2.]$
Using R, we get the CI $(40.04,\, 70.12)$ for $\sigma^2$ from a sample of size $n = 100$ from a normal population known to have
$\sigma^2 = 49.$
<code>set.seed(131)
x = rnorm(100, 50, 7)   # norm samp size 100. var 49
CI = 99*var(x)/qchisq(c(.975,.025), 99)
CI
[1] 40.05443 70.11714   # 95% CI for pop variance
sqrt(CI)
[1] 6.328857 8.373598   # 95% CI for pop SD
</code>
(2) $E(S^2) = \sigma^2,$ but for normal data $E(S) < \sigma.$  The bias of $S$ as an estimate of $\sigma$
is especially noticeable for small $n.$
The following simulation in R, using a million samples of size $n=4,$ illustrates the bias of the sample standard deviation $S.$ (Any one normal sample of size 4 can have an unusually large or small standard deviation. However, by looking at a million samples, it becomes clear that the bias is toward values of $S$ that underestimate $\sigma.)$
<code> set.seed(2022)
 n = 4;  sg = 15
 s = replicate(10^6, sd(rnorm(n, 100, sg)))
 mean(s)
 [1] 13.81432  # noticeably smaller than 15
 mean(s^2)
 [1] 224.8197  # approx = pop variance 225
</code>


How do I sort by day?

Question: Hi I have a bunch of items which occur on a given day of the week. So i have a text field called Day, and it's populated by the words 'Monday', 'Tuesday', 'Wednesday' etc. Is there a way to sort this in views that will list items in Weekday order. I can only find options for alphabetical order.
Comment: These sound like strings, so, no you can't just sort by order of days in the week. They'd have to be taxonomy at a minimum, sorted by taxonomy order.
Comment: You need to group, see https://stackoverflow.com/a/13829576
Answer: This could be working for example if you'd use a taxonomy term reference instead of a text field. Just create a taxonomy with your workdays as terms.

use these tags on your content
in views add a field to show the term your content is tagged with
in the format options choose 'group by' and select your taxonomy field

Now the content should be grouped by the workdays. To achieve the correct sorting order you can either rely on the term-ID (which is created in chronological order) or just arrange your terms with drag and drop (in the terms dialog).

How do I sort by day?


Display excel grid lines in front of a chart?

Question: I have an area chart in Excel for Mac 2011 that I'd like to display grid lines in front of.  Is there a way to do this?  I know I could make the chart semi-transparent and show the grid lines through, but doing that makes the graph a bit hard to read.
Answer: You best bet is to make the area series semi-transparent. This helps show the gridlines, and also makes the area fill colors less dark than the defaults (which are generally too dark).
Comment: I don't like using solid black gridlines, since that draws attention from the actual data. But transparent areas and bars also work with the default medium gray gridlines.
Comment: I've found setting transparency to 10% and major gridline color to black works well as a good start
Answer: Not possible I'm afraid. The grid is in a different layer to the chart but the same layer as the cell data. Transparent background to the chart is the only option or a semi-transparent overlay image (messy).
Comment: He doesn't mean the cell boundary gridlines, he means the axis tick gridlines.
Answer: Alternatively (and a bit bulky) you could put an x-y chart on the second axis (I believe by default the 2nd axis displays on top of the primary axis) and connect points with lines to create your own gridlines.
Hard to manage, though.
Comment: Or error bars, or whatever. A bit bulky, is right.


My UK visa has been refused please help I want to re apply

Question:  every month in my bank statement I transferred money to my cousin to save and he transferred it back before my visa....
Comment: @Alexis Ashman Do the entries in your bank statement show the money leaving your account and being transferred back? That pattern makes little sense - why not just save the money in a separate account in your own name? Why did your leave letter show longer time off than your planned visit? There's no point re-applying unless you can clarify all of the refusal points and provide suitable evidence.
Comment: @Traveller Presumably, the asker wanted to avoid the temptation to spend the money themself.
Answer: To summarize:

You want to spend practically all of your savings on a trip to the UK
You plan to visit for 55 days and take 90 days off work, long periods of time that raise the question of how you'll support yourself after spending all your money on a trip
Your bank statements show suspiciously unexplained transactions because you transfer money back and forth between your account and your cousin's

None of this is a recipe to be granted a visa right now. And if you're refused again, you'll start to develop a record of serial refusals that could hurt your case; you don't want to look desperate to get into the UK.
I'd wait to reapply until you have your situation at home more in order. Read Should I submit bank statements when applying for a UK Visa? What do they say about me? and aim for stable finances that show a history of salary deposits and greater savings, without unusual transfers (or if you do have necessary transfers, with documentation to show where the money is coming from and why you're receiving it). Have a clear explanation for the amount of time you'll be away, an amount that makes sense in proportion to your economic circumstances. Build up sufficient savings so that you won't be emptying your bank account to afford the trip. At that point, you'll have a greater chance of success.
Answer:
You can reapply with in 28 days of refusal with the same sponsorship documents , but you will have to satisfy the ECO;
You will have to get new letter from your employer with the specific dates of visiting abroad. You may ad up 3/4 days
Your bank transaction in November does not consistent with the previous deposit history. So you should explain satisfactorily that why the transaction history is different with the past.
The ECO is not satisfied with the origin of the funds specifically shown in  NOV.
If you think that you can satisfy the ECO on the above matters you should reapply , otherwise wait till your circumstances are changed
Comment: While this answer is longer than your other answers, it also lacks all links and quotes, all proof that this is more than just your imagination.


php pcntl_signal with proc_open

Question: I have a custom php script that opens a third party perl script using proc_open.  I was trying to put in some pcntl_signal handles so I could cleanup gracefully on an interrupt.
I'm able to get my signal handler to work in more confined test beds where it's just spinning in a loop or something.
However when it's looping through the child script w/ proc_open a CTRL+C seems to just completely die right there.  To be clear I mean complete immediate stopping of both the parent and child process.  It's not as if the ctrl+c is is being caught by the 3rd party child process, returning and my script continues.
I've read in the php docs it's known signal handling doesn't play well with things like sleep() and figured it might be something similar w/ the POSIX proc_open functions.  Looking over SO there seemed to be a few similar posts with a solution to either move signal handling in a child process or toggle the restart_syscalls param to proc_open, depending on the situation.
I've tried toggling the restart_syscalls param to false but that didn't do me any good.
Unfortunately the child process is a 3rd party script so I'm not familiar with the actual code.  Before trying to muck around in that to get signals propagated back up (if that's possible or even the thing to do) I was wondering if there's something missing with my setup that so I could maintain just my code.
What I have looks like
<code><?php

declare(ticks=1);

class signalHandler{

    public static function handle($signal){
        throw new KillException("Received Kill signal $signal", $signal);
    }

}
pcntl_signal(SIGINT,array('signalHandler','handle'));
</code>
Then later on, calling the actual child process:
<code>$childCmd = "thirdPartyScript.pl";

// Set up how we'll interact with the IO file handlers of the process
$descriptors = Array(
    0 => Array('file', '/dev/null', 'r'), // Process will read from /dev/null
    1 => Array('pipe', 'w'), // Process will write to STDOUT pipe
    2 => Array('pipe', 'w')  // Process will write to STDERR pipe
);

// Start the process
$childProc = proc_open($childCmd, $descriptors, $pipes);

// Check the status of the backup every second...
$streamContents = '';

stream_set_blocking($pipes[2], 0);
do {
    $streamContents .= stream_get_contents($pipes[2]);

    if( ! ( $childStatus = proc_get_status($childProc) ) ) {
        throw new Exception("Error: Unable to retrieve status on child process.");
    }

} while ($childStatus['running']);
</code>
Answer: You should listen to SIGCHLD too, if you want to be notified when your child dies.
I think that you can also put safely for example sleep(1) inside the polling cycle to reduce busy work.

php pcntl_signal with proc_open


WGCNA soft threshold selection

Question: Here I am conducting WGCNA analysis. When calculating the soft threshold, it is basically below 0.8. I choose Power=6, which only has 0 and 7. Is it feasible?
Comment: Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.
Comment: Please copy-paste text as text into question posts. This makes the text easier to read on some devices, and allows it to be more easily modified when required.
Answer: I don't know the context (how many samples, what tissue, experimental design etc) but the mean and median connectivities are pretty high at power 6. I would first check the data for strong drivers of correlation and possibly adjust for them if they do not seem biologically relevant to the question you study. Assuming you find no issues, I would go with a higher power here, maybe 12.

WGCNA soft threshold selection


Is forwarding rate important for selecting a collapse core switch in IP camera implementation?

Question: I need to select a core switch that will connect my access switch to an IP surveillance's server. The point is that in my network I'll have 109 IP camera sending real time traffic to the server and I'm not sure if I have to consider the amount of packets per second (mpps) that can handle the core switch.
Answer: Modern switches are generally non-blocking, ie. they can forward as fast as their ports allow them to (large, modular chassis switches may have a lower backplane capacity than the maximum number of the fastest modules would allow).
This holds true for both bandwidth capacity and forwarding capacity. E.g. a switch with 48x 1G and 4x 10G ports should support a maximum throughput of 88 Gbit/s (or 176 Gbit/s aggregating ingress and egress) or 131 Mframes/s (the smallest frame uses 84x8=672 bits on the wire).
Basically, you just need to multiply a camera's average bandwidth (including overhead) with the number of cameras. The number and size of packets doesn't matter. Also, if a camera runs an average of 2 Mbit/s they just add up to 220 Mbit/s which is a piece of cake.
Comment: So, if the bandwidth of one camera is 10Mbit/s I just need to make sure that my core switch must have a bandwidth capacity greater than 1.1 Gbit/s (as you said, all moderm switch generally support that value), regardless the forwarding capacity in this case?
Comment: Practically, yes. Make sure the server can handle the load and its port(s) get(s) sufficient bandwidth.


Topology of boundaries of hyperbolic groups

Question: For many examples of word-hyperbolic groups which I have seen in the context of low-dimensional topology, the ideal boundary is either homeomorphic to a n-sphere for some n or a Cantor set. So, I was wondering if this is generally true or there are some examples of hyperbolic groups whose boundaries are neither a sphere of some dimension nor a Cantor set. If there exist such examples, is there any known topological classification of boundaries of hyperbolic groups?
Comment: The class of discrete hyperbolic groups is stable under free products, this provides low-cost examples with a different boundary. For more refined ones, see this survey by I. Kapovich and Benakli: http://www.math.uiuc.edu/~kapovich/PAPERS/bry1.pdf
Answer: There are plenty of other possibilities. Here are a few examples:

The boundary of the fundamental group of an acylindrical hyperbolic 3-manifold with totally geodesic boundary is homeomorphic to a Sierpinski carpet. (This appears in the Kapovich and Kleiner paper mentioned below, but must be standard---the point is the topological fact that any planar continuum with no local cut points is homeomorphic to a Sierpinski carpet.  Indeed, they prove a converse result, modulo the Cannon Conjecture.)
The boundary of a random group is homeomorphic to a Menger sponge (Dahmani--Guirardel--Przytycki).
Bowditch proved that cyclic splittings of $\Gamma$ correspond to local cut points on the boundary.  In particular, the boundary of a graph of free groups with cyclic edge groups can be decomposed along cut pairs into Cantor sets.

The classification of 1-dimensional Polish spaces implies that this is a complete list of boundaries of 2-dimensional hyperbolic groups, in the sense that if the boundary is connected with no local cut point (ie the group has no splitting over a virtually cyclic subgroup) then it must be a Sierpinski carpet or Menger sponge (Kapovich--Kleiner).
I imagine that a classification in higher dimensions is completely out of reach, though I'm no expert.  (Misha Kapovich is active on MO and can provide an authoritative answer.)
I'll add full references tomorrow.
Comment: Thanks a lot, Henry. This is very interesting. I wonder if there is any partial result in classification of boundaries of 3-dimensional hyperbolic groups.
Comment: @harry: what do you mean by "3-dimensional hyperbolic group"? there are many inequivalent notions of dimension.
Comment: @Yves, in this case, the natural definition of dimension for a hyperbolic group $\Gamma$ is the topological dimension of the boundary +1.  As you say, there are other relevant definitions.  It's unknown which hyperbolic groups have boundary of conformal dimension 1, for instance.
Comment: @YvesCornulier: Yes, I just meant the topological dimension of the boundary + 1.
Comment: @HJRW I think you mean [Sierpinski carpet](https://en.wikipedia.org/wiki/Sierpinski_carpet) as opposed to [Sierpinski gasket](https://en.wikipedia.org/wiki/Sierpinski_triangle).  (The latter term is a synonym for the Sierpinski triangle.)
Comment: @JimBelk, I do -- thanks for the correction.