What, if any, storylines did The Dark Knight Rises borrow from?

Question: The Dark Knight Rises sees Batman fight

 Bane and Talia al Ghoul, who are part of a plan to finally complete R'as al Ghoul's mission of burning Gotham to the ground.

What, if any, storylines in the comicbooks did The Dark Knight Rises borrow from?
Comment: Related: [Is Batman Begins based on any Batman comic or was it entirely written from scratch?](http://movies.stackexchange.com/q/761/49)
Answer: It pulls elements from multiple Batman arcs, like the other Nolan Batman films have.
The obvious one is Knightfall.  This storyline introduced Bane to the comics, who proceeds to wear down Batman by freeing all the occupants of Arkham Asylum and eventually confronting him personally.  During that confrontation, Bane famously breaks the Bat.  This leaves Bruce a paraplegic, who spends a chunk of the storyline recovering, while having someone else take the mantle of Batman.
The next storyline that it pulls from is The Dark Knight Returns, which has an elderly Batman return after a decade of being retired.
The last one is No Man's Land.  Following a devastating earthquake in the storyline leading in to No Man's Land, the government evacuates Gotham and abandons those who choose to remain.  It's sealed off, and all bridges into the city are blown up.  People are then forbidden from entering or leaving the city.  Inside the city, Jim Gordon and some cops remain, and they struggle to maintain order.  Batman and allies fight the gangs who are battling for control over Gotham.
Answer: The obvious influence is the Knightfall story arc.  This introduces Bane and includes the part where Bane injures Batman's back.  A link could be drawn between the prison breaks in both movie and comic, but that is tenuous given the standard of prisoners released.
Batman has a romance with Talia Al-Ghul in the Son of the Demon story arc but with a significant difference - Batman is aware of who Talia is in that.
Answer: He might have borrowed from the Death of Batman story arc as well, where Batman presumably dies from an explosion at sea.  In the comics it is a helicopter,  the movies it's a nuclear blast. He doesn't really die in either, but it's a fun little coincidence.
Answer: Knightfall, No Man's Land, Legacy, Batman: The Cult, Dark Victory, The Dark Knight Returns... Honestly thats not even all of them. Chris and Jonathan Nolan very obviously read the entire Modern Age run (which I've been trying to do) and took things, even sometimes almost unnoticeable things from many storylines. People don't usually mention The Cult, but it is just as much of an inspiration as Knightfall, NML, and DKR are once you read it.
Comment: I like this answer, but I doubt the Nolans read any of these.  It's much more likely that David S. Goyer read them and then haphazardly mashed them together for the Nolans.
Comment: @Praxis [I highly doubt that](http://movies.stackexchange.com/a/34999/49).
Answer: Having Bane as the main antagonist of the film, his comic origin story 'Vengeance of Bane' was sourced. The story details how he was born in a prison for the crimes of his father and would escape as an adult. The iconic moment of Bane breaking Batman over his knee, was paid homage to from the pages of 'Batman #497' (Knightfall).
Having said that Bane's actions in the film, mimic those mostly of the villian Deacon Blackfire. He features in 'The Cult', which seems to have influenced the film the most. Gordon is hospitalised and visited by Batman, an underground army of homeless rise from the sewers to take Gotham by force in a uprising lead by the charismatic leader. Batman is imprisoned underground too. Many more elements from this comic feature in the film.
'The Cult' is as much as an inspiration 'Year One' is to Batman Begins or 'The Long Halloween' is to The Dark Knight.


Intermittent error code 400, description "" on client connecting to channel

Question: My Google App Engine app, which uses the Channel API works well some of the time. Intermittently, though, the js code connecting to the channel generates an error. In socket.onError, the error code is set to 400 and the description is set to an empty string. I have checked that the token being used to connect is valid. I also tried recreating the channel in socket.onError, by first calling socket.close() but that does not seem to work. Often there is a series of failures before a success. The client js is running on Safari on iOS. Any ideas on how to fix or work around the problem will be welcome. Right now, my best workaround is to keep trying till I succeed, increasing the interval between attempts on each failure. The server side presence API does not help, since the 'connected' hook is not called reliably.
Answer: It is known issue http://code.google.com/p/googleappengine/issues/detail?id=4940 and it was accepted. As you see the status of issue is not fixed. Feel free to star it.
Comment: Thanks. In response to the comments in that issue:
1. I tried the proposed workaround of "pinging" an established channel but found that it does not prevent the error.
2. Resetting the client id does not help, sometimes the error occurs with new connections.
Answer: I know double posting is bad (issue starred & comment posted)... but I suspect this thread might get more attention than the issue comments ^^
As far as we are concerned, it's at the very least a documentation issue:
https://developers.google.com/appengine/docs/java/channel/javascript still
states " An onerror call is always followed by an onclose call and the channel object will have to be recreated after this event"
It is only true for, as far as we have guessed, error codes 400 and 401 (which are strings, not numbers, btw, so beware of === in the js code).
It is untrue for other error codes (we have logged at least the -1 code).
There should be a documentation covering all error codes and their (expected) management.
Atm, we have a "channel manager" that reuses the same channel token when code is not 400 or 401, and that makes sure onclose is called once and once only per Socket.
Before that, we were trying to close properly, and reopen (new underlying Socket) with a shiny brand new token: usually we got an error 400 followed by an error -1.
FUI we first detected this behavior on iOS, quite recently (regression ftw? Before that iOS was dandy). Reopening the socket after a code -1 is not a panacea: sometimes it will succeed (onopen properly called), and then fail silently (no message received, no onerror called).
Generally, we also noticed more consistent behavior on desktop browsers than mobile ones, across all user agents and platforms (more on that: yay! Other issues incoming! Especially android...)
OK, this post might have been useful after all. Thx!
[EDIT: corrected a mistake... we don't reuse the channel object nor the socket object, only the token]
Comment: 1)a) Yes. That means we explicitly call the close method of the goog.appengine.Socket object if our internal state allows it (see below). Then we recreate a Channel then a Socket object, etc. (the whole workflow)
Comment: 1)b) After creating a Channel object we pass an object containing the 4 expected callbacks (onopen, onclose, onmessage, onerror) to the open method. The callbacks are all closures that allow us to maintain a global consistent state for the "current channel environment". Use your own preferred pattern... ^^
Comment: 2) When we get an error that we don't interpret as "token expired or whatever => need a new token", we do exactly the same (close, recreate, reopen) but with the same token. We don't reuse the same underlying object, sorry for the confusion...

Edited main post to reflect that!
Comment: I am observing this problem on iOS also. Have you resolved the issue on iOS using the method outlined above? If so, then could you clarify your solution. As I understand it: 1. For errors 400 and 401, you a) recreate the socket. b) ensure that onClose is not called twice 2) For error -1, you 'reuse the socket' (what does that mean exactly)?
Comment: I tried your method, but it does not address the issue for us.
Answer: I contacted Google support about this issue.
When a error 400 happens it's because a timeout (one minute it seems) happened. This timeout generates a disconnection  (url disconnected is called and you should remove the client id of the database).
Then, a new channel must be created with a new client id.
But it is not enough. We have to use this jquery command line : $('#wcs-iframe').remove();
Just inside the js onerror function and before to try to recreate the channel.


Ubuntu Installation over windows 7

Question: I am trying to install new Ubuntu version 18.04.3 on my window 7. After i have made a setup in USB its running fine on USB but when i try to install it on my system after successful installation and restart it still asks for Ubuntu installation option and when i remove USB it is not working properly. I have used 'something else' option and made new partitions so no old data or Windows on the PC left. Any suggestions please?
Comment: Thanks for the replies. Its working fine now so far. What i am doing wrong was not selecting HDD as first option after restarting system. I should make Hard Drive option as first one instead USB Drive.
Answer: Thanks for the replies. It's working fine now so far. What I was doing wrong was not selecting HDD as the first option after restarting the system. I had to make the Hard Drive option as the first one instead of USB Drive.

Ubuntu Installation over windows 7


How many times can you format a hard-drive?

Question: I've read mixed cases all over the place regarding the life of a typical hard drive, and if reformatting degrades the disk. If so, could you measure the life of the disk in a practical manner or explain how it can be damaged?
Comment: The world may never know.
Answer: Reformatting any modern hard disk is no different from normal use of the same amount.  You cannot actually lay down any track information.  Modern hard drives are formatted at the factory using special connectors or special equipment.  When you format a modern hard drive, at most you fill the drive with all zeros and maybe map out some sectors that were discovered to be bad.
You will not wear a hard disk out by reformatting any more than normal use will wear it out.
If you are talking about something extreme like continuously formatting a drive, this should be about the same as any continuous read/write access to the drive.  You cannot degrade the magnetic medium in any way by doing this, as long as the drive is adequately cooled.  A drive that runs at an extreme temperature will definitely have a degraded lifetime.
SSD drives are a different animal where each write gets you closer to eventual failure.
Comment: As I understand SSD drives, though, the theoretical lifespan of the disk is still so high that by the time it's an issue it's time to replace the drive...like after years and years of average disk use...and under conditions that cause mechanical failure in normal drives. That's my understanding, anyway.
Comment: Just keep in mind that reformating means mostly writing to the same sectors. If a drive doesn't have a proper remapping blocks policy it may be a problem.
Answer: Measuring the life of a hard drive is like measuring the life of a light bulb.
Once you know how long it lives, it doesn't anymore ;-)
Answer: Reformatting a magnetic hard disk should not degrade the disk any more than any other use of the drive. The drive may even notice and relocate bad sectors as the head has an opportunity to revisit rarely used portions of the platter, but if I wouldn't count on reformatting providing any benefit other than an empty filesystem.
Answer: From a drive's perspective there's no difference between writing data to a drive and formatting it. In general, many of the same physical sectors written to during a format will also be written often if you are using the filesystem heavily ("FAT" table, or equivalent, directory structures, etc.) For magnetic disks, I wouldn't worry about formatting as a possible contributory factor to drive failure. I've had experience with dozens of machines that have their main OS drives reformatted several times a day on overage over the course of 2+ years and show no signs of excess drive failure.
Answer: If it is not a SSD drive, on which there is a limit (far higher than it used to be, though), regular (a.k.a quick) formats to the drive usually don't erase data, altering only the sector dedicated to the FAT, causing "uneven" wear, if you like.
Practically, I have yet to encounter a single case of even a mention to this issue.
Answer: A typical "quick" format on a typical filesystem isn't a big deal - it only writes a few blocks.


How can I protect my pigs so they don't become pigmen?

Question: My pig has just turned into a zombie pigman. I have tried putting them inside, but they still turn into the pigmen!
Comment: Are you sure a pig turned into a zombie pigman? They only turn into zombie pigmen when hit by lightning. Do you maybe have a nether portal nearby? Those spawn zombie pigmen.
Comment: @SevenSidedDie No there is no portal nearby and they are inside a wooden hut. They are definitely pigmen.
Answer: Lightning only strikes straight down, but can transform a pig within 3-4 blocks of the lightning strike. Therefore, to keep your pigs safe from lightning storms, their shed has to be built so that it keeps them at least 5 blocks away from the outside sky. Building a 5 block wide overhang around the shed roof should do it. Alternatively, make your barn so that the pigs are in an inner chamber, with less "volatile" livestock like chickens and cows in the chambers near the walls.
Comment: I love the idea that a barn full of pigs got struck by lightning, and when you opened the door to feed them the next morning, ARGH ZOMBIES! Ripped straight from a Romero movie.
Answer: Dig a 5 by 5 hole 10 blocks deep, and build stairs with a door at the top so the pigs wont get out. Put torches so no mobs can spawn, and build a roof out of any material except wood.
Answer: It's probably the lightning. You should probably put your pigs underground if it happens a lot. It never happens for me though. Not once. But try putting them underground, or just keeping them indoors, so lightning doesn't hit them.


Can I use coaxial cable for audio over 30 feet?

Question: Want to buy a mid range AV Reciever model, but my concern is that can I provide input audio from another room(away from 30feet) by coaxial cable (or only RCA audio cable required). 2nd, for output can I use coaxial cable (30 feet) for bathroom (without amplifier) without any qauality compromise.
Answer: RCA audio cables are normally coaxial in construction, and are fine out to 50 feet or more, normally. I've run 100+ feet when needed for auditorium A/V setups. While there are fancier ways to go long distances, with modern equipment and cables there's little need for them in most cases.
Most coaxial cable is not particularly suited to use as "output, without amplifier" - ie, speaker cable use. Use speaker cable for that job, it's what it's made for.


HTTP Error 503 the service is unavailable

Question: When I open Central Administration I get this error

HTTP Error 503. The service is unavailable.

Same error also when I open my SharePoint Server 2010 site

HTTP Error 503. The service is unavailable

How to resolve this?
Answer: When you run into the issue "HTTP Error 503, the service is unavailable" when you launch the website through IIS (Internet Information Services), you will end up seeing the following message:

To remediate the issue, you will need to open IIS Manager (inetmgr.exe). This error is caused because specific website Application Pools were stopped or disabled by a certain circumstance. You will need to select the Application Pool, for the affected Web Applications, and hit Start. Once completed, please revisit your web application.

Note: If the application pool continues to stop, please verify that all SharePoint services are started, this error might occur because of changing the service account password. You may need to change the new password for the application pool or sharepoint timer service.
[ Source ]
Answer: Please, ensure, that the IIS application pools that belong to these SharePoint web applications are up and running. If they are running, you can try to restart them.
Often it happens as you install a new solution into the SharePoint farm. Most of the time this issue is only temporary (1-2 Minutues), but can be quite frustrating.
See this post as reference.
Answer: Goto IIS manager ->Application  Pool,
click stopped application pool like 'SharePoint Central Administration v4'
Right click Advanced settings,
and set "Enable 32-bit applications" to "False"
More info
https://social.msdn.microsoft.com/Forums/office/en-US/c960aa7f-e7dc-4400-9067-377e8d537c90/service-unavailable-http-error-503-application-pool-stopped-for-the-web-appliaction?forum=sharepointdevelopmentprevious
Answer: Click the stopped application pool -> click advanced settings ->Identity ->click the user to retype the user ->Application Pool Identity dialog ->click set -> manually type the user name and password. Then restart the server.


Unequal variance and sample size?

Question: What is the effect of sample size on variance? If $n$ in two groups is different, does that automatically mean variance is not equal?
Comment: The population variance has nothing to do with sample size.Sample size  affects the accuracy of the estimate of variance. There is an F test that can be used to test equality of variances based on the assumption of independent normal distributions.
Answer: Outside of extraordinary coincidence, the variance of two samples from the same population will be unequal even if your sample sizes are the same. That your sample sizes differ does not cause this disparity, but can exacerbate it, particularly in extreme cases. The sample variance is always biased, hence the correction usually employed.

Unequal variance and sample size?


Difference Between Exposure, Brightness, and Brilliance Settings

Question: On the iPhone, the built in photo lighting adjustments includes exposure, brightness, and brilliance. They are all slightly varied settings, but it's hard to really tell what's exactly going on. What is different about these settings that makes each one unique?
Answer: Elaborated from macworld.com, and some of the other answers here.
The key difference to these methods that will be true for both iPhone and photo editing more generally, is the application of brightness to particular ranges on the spectrum of black/dark to white/bright in your photograph. (A histogram shows this.) Methods vary as to whether they are increasing values in a specific range only, and they may vary in how much is being increased.

Exposure increases the pixel value brightness equally for all parts of the picture.

Brightness and Brilliance also increase the values, but to only a selection of the image. What I don't know is the method of subsetted pixels being transformed. I'm reading between the lines, full disclosure.

Brightness increases those pixels that are not already extremely bright (close to white), in contrast to exposure, which would also increase the brightness of those extremely bright pixels.

Brilliance is likely (I can't find details) using an algorithm that gives a variable amount of increase as a function of the distribution of light already present in the picture. For example, increasing a little, a lot, a little and none to medium, medium-bright, bright, and very bright parts of the picture.
Answer: From Apple's support documentation:
Brilliance: Adjusts a photo to make it look richer and more vibrant, brightening dark areas, pulling in highlights, and adding contrast to reveal hidden detail. The adjustment is color neutral (no saturation is applied), but there may be a perceived change in color because brighter images with more contrast appear more vibrant.
Exposure: Adjusts the brightness or darkness of the entire image.
Highlights: Adjusts the highlight detail.
Shadows: Adjusts the detail that appears in shadows.
Brightness: Adjusts the brightness of the photo.
Contrast: Adjusts the contrast of the photo.
Black Point: Sets the point at which the darkest parts of the image become completely black without any detail. Setting the black point can improve the contrast in a washed-out image.
Comment: This is a good start, but the quoted text doesn't help explain, for instance, Exposure ("Adjusts the brightness or darkness of the entire image") vs. Brightness ("Adjusts the brightness of the photo"). How do those two adjustments differ?
Answer: Not an answer because I don't know details of the iPhone, but there are four ways (four to my knowledge) to "brighten" an existing image.

Most usual Brightness sliders in photo editors simply slide all the data up by adding a given constant to all pixels. If you go very far, this can of course heavily clip data at 255.  Not the best way.  If you add 30, then 0 becomes 30 (not black) and 255 becomes clipped by 30.
Much better is to adjust gamma, for example, the Center slider in Adobe Levels.  Gamma has the property of fixing both end points, they cannot possibly move, so you can brighten the dickens in one with zero risk of clipping.  Also meaning no dynamic range change,  just brighter.
The White Point in Levels is a very common method (is also the Exposure slider in Adobe Camera Raw). It sets a new white point. For example, sliding white point down from 255 to say 220 says to boost the data so that the previous 220 data will become 255. This of course clips anything in between, but that point was visible and studied in the histogram (i.e. it is our choice). Then the adjustment of the rest of the data is a curve not exactly the same as linear exposure, but except at the highest end, it's probably within 1/3 stop of a linear change.
The Photoshop menu Images - Adjustments - Exposure has an Exposure slider that adjusts by actually calculating new values for a given linear exposure boost.  +1 EV raises all values by +1 EV.  This is pretty uncommon.  Photoshop offers all of the methods.

A curve tool can mimic 2. and 3.
You could study the changes each iPhone choice performs, and probably figure out which is which.  It would seem most important to know what both end points do.
Comment: Fair that the post starts as 'not an answer', but thus it shouldn't be posted as one. OP asks for clarification of the underpinnings of 3 settings on an iPhone. It could be reasonable to give the analogous 3 settings in, e.g., Adobe, but discussing Adobe's White Balance and gamma features are clearly outside the scope of this question.


Papervision3D books to buy

Question: Can anyone suggest me a good papervision3D book to read? I know as3 pretty well but I'm just starting out with pv3d.
Answer: Don't know of any books currently in print, but Amazon shows a promising looking book from Wiley - Professional Papervision 3D coming out on October 19th.
Other than that, I've mainly used the resources on pv3d.org and the API docs
Answer: I have been enjoying "Papervision3D Essentials" by Tondeur and Winder.  It's available now (at the end of 2009) and one of the chapters (chapter 8, on loading a Collada model) can be downloaded free.
Professional Papervision 3D looks good, too -- many of the code samples are available on the author's blog -- but it is still in the publishing pipeline for awhile.
Answer: Professional Papervision3D was released recently. But there is also another interesting book in the making by Apress/Friends of ED. It's called "Experience Papervision3D". As far as I could find out the authors will be Seb Lee-Delisle and Carlos Ulloa, two of Papervision3Ds core team, which makes it probably worthwhile waiting for its release. Unfortunately there is no information when this book will be available. To my knowledge the earliest date will be April 2010. Right now the book cannot be found on the Apress Site as well as on the Friends of ED Site. Only Amazon is listing it as "currently unavailable".

Papervision3D books to buy


Xubuntu 16.04 installer hangs at "Configuring system locales..." on VirtualBox

Question: LTS Xubuntu 16.04.3 (64-bit) hangs while installing in VirtualBox 5.2.0 r118431 (Qt5.6.2) on Windows 10. See screenshot. The latest Lubuntu and TinyCore worked fine, (but respectively lacked consistent resolution and popular package support) so it's not a VirtualBox issue. I tried pressing escape and clicking stuff, but nothing moves aside from the animated busy cursor. The idle screen blanking also works.
Comment: Did you check the hashsum?
Comment: @Panther I'm assuming uTorrent already did, as it's seeding the iso on my wired 200/20 Mbit connection.
Answer: You should be able to find out what's going on by pressing CTRL-ALT-F1 inside the VM. That should bring you into a console. Try out ALT-F(any of the function keys) inside the console.
There should be different consoles showing different things, among others some debug output on what the installer is doing. You should be able to find out what it's doing or respectively where it's stuck by looking around there.
Also there should be a shell there. You should be able to issue a ps auxw or similar to find out what's going on.
Comment: I've already reset and am reinstalling with different settings, but will try to redo my original course tomorrow.
Answer: I've reset the VM and with these different choices it appears to be installing:

Try Xubuntu instead of Install to disk.
Don't download updates while installing.
Don't use LVM.
Don't encrypt home folder.

The slideshow completed and right now it's "Copying files...". Pressing the arrow to the left of that status shows it's failed to load module "overlay-scrollbar" but the progress bar goes on, slowly. Attempting to load the display settings to up the resolution to see the full details leads to a segfault:

The crash report details contain the correct time, but the task bar time is an hour behind:

At 21:54 (actually 22:54) installation completed and i continued to test the display settings again. Same internal error. Sent error report again and restarted the system. Pretty animated splash screen asks to remove installation medium, but apparently VirtualBox already did. Entering a jarring black screen with one text line, occasionally interrupted by the splash screen. Logging in to a very clean desktop... And there are the 3 icons and wallpaper. Trying display settings again... Same internal error. Oh well, at least it supports deb at more than 640x480.
Comment: After installing the VirtualBox Guest Additions from the CD and restarting, the resolution fit the window and the display settings work.


My sculpting brush doesn't work - I'm a beginner

Question: I started using blender yesterday so probably this isn't a hard problem to solve, but I have no idea what happened. I sculpted a few times before and then I edited a few things in layout and then I went back to sculpting and since then my brush doesn't work/it has no effect (so no matter how many times i click, it doesn't do anything). Maybe i used a shortcut accidentally? Or did I do something with my settings? I tried to watch tutorials but they didn't help, probably because i don't know what is the problem is exactly.
Comment: hello, please share your file (copy paste the link it will give you): https://pasteall.org/blend/
Comment: https://pasteall.org/blend/fe6070b0a50c48bf95a499a38e078d81 @moonbots
Answer: First select something that you can see (like Plane.002), then, in the N panel, under Brush Settings, close the texture, otherwise you won't be able to paint anything as your texture is completely black:


Are those with access to moderator tools allowed to moderate their own posts?

Question: As per the title, are mods (and non-mods with semi-mod powers due to high privileges) notified and/or allowed to moderate their own posts which others have flagged?
Answer: Only actual ♦ moderators can see a summary of all flags and act on these (i.e. dismiss as helpful or decline them).
Users with 10k privileges see a subset of flags and may act on them by flagging the posts another time or disputing the flags. They cannot, however, act on these flags in any other way. As a consequence, "normal" users with 10k reputation cannot see flags on their own posts and can therefore not act on them.
Since moderators see all flags, they also see flags on their own posts. This means they could also act on these flags, although I guess many moderators would leave flags on their own posts to be handled by another moderator for the sake of fairness and transparency.
Comment: Good to know, thanks. (Also, I would suppose most mods here would think it's bad form to moderate their own posts.) I briefly considered the idea that the name of the mod who responded to a flag should be displayed as well, but I think that's just going to cause needless resentment so it's not a good idea at all.
Comment: Yeah, I'm afraid that'd do more harm than good. If there's a flag decision you don't understand, you're free to flag again, ask on Meta, come to chat, et cetera. It's always easier to settle things then, and we should be focusing on the content, not the moderator who handled it.
Comment: "we should be focusing on the content, not the moderator who handled it" - Yes, absolutely, which is why I knew it was a bad idea. Ideally speaking, all mods should behave in a similar and more importantly, consistent manner so that to users it does not matter who specifically did what.


How do I use user_helper method globally throughout the app views?

Question: I finished chapter 8 on Michael Hartl's Rails Tutorial, so I have the app set up to sign users up & sign in and out.
What I am trying to do user a User Helper method inside the application.html.erb (or more specifically inside a _header.html.erb partial).
I want to use the gravatar_for method (Defined in the user_helper.rb) to show the user's gravatar picture and users name instead of having the word "Account" with the drop down.
module UsersHelper

  # Returns the Gravatar for the given user.
  def gravatar_for(user, options = { size: 150})
    gravatar_id = Digest::MD5::hexdigest(user.email.downcase)
    size = options[:size]
    gravatar_url = "http://gravatar.com/avatar/#{gravatar_id}?s=#{size}"
    image_tag(gravatar_url, alt: user.name, class: "gravatar")
  end
end

On the show.html.erb page I have the following code
<% provide(:title, @user.name ) %>

          <%= gravatar_for @user %>
          <%= @user.name %>

And that shows the user's gravatar and name on their profile page. So what I tried to do was add those same methods to the header partial like so;
<% if signed_in? %>

        <%= gravatar_for @user %><%= @user.name %>

<%= link_to "Profile", current_user %>

<%= link_to "Settings", '#' %>

<%= link_to "Sign out", signout_path, method: "delete" %>

<% else %>

<%= link_to "+ Sign up",  signup_path %>

<%= link_to "Sign in", signin_path %>

<% end %>

And that code shows up completely fine on the show.html.erb page, which I am assuming is because its the show action on the Users controller. But when I try to click to the home page or really any other page outside of the Users View then I get the error
NoMethodError in Pages#about
undefined method `email' for nil:NilClass

So I guess my question is how do I make the gravatar for method and the @user.name available to all the views throughout the application. I feel as if the answer should be fairly simple, but i'm pretty new to rails, so any help would be greatly appreciated!
Answer: Put the method in the ApplicationHelper instead of the UserHelper. Here is an example of something similar I did in my own app: https://github.com/NatashaTheRobot/tinysale/blob/master/app/helpers/application_helper.rb


Why are DSLR lenses measured in F stops instead of T stops?

Question: I understand the difference between f-stop and t-stop, but why are cinema lenses measured in one, and dSLR lenses measured in another?
Answer: Because in cinema, it's common to change lenses within a shoot while preserving identical exposure. This is rarely important in still photography (and even less so with the flexibility of digital).
You might say But t-stops are more accurate, allowing me to be more precise! — and that's basically right, but the main thing is that precision is overrated in photography. Generally, if the difference is under a stop, it's easy to compensate without much consequence, and if it's under a third of a stop (a typical variation in t-stops), it's barely noticeable — but if you saw that change in a film, it might jump out at you.
Presumably the transition of cinema from film to digital also makes this less important, since it's easier to fix it all up in post. (That's the answer to everything, right?) But that's not an area I really know anything about so I'm just speculating.
Of course, transmission is not everything. Aperture also influences depth of field, too — although I would argue that this doesn't matter too much in terms of labeling either, for basically the same reason of precision: subject (and focus) distance, print viewing size, and all the factors which affect depth of field mean that just knowing the f-number doesn't give you more than a general idea of results. (And that's not even considering that numbers are often rounded.)
Comment: T-stop is not just a "better" F-stop, T-stop gives you the precise exposure value but F-stop reflects the precise aperture (depth of focus, bokeh).
Comment: Totally agree, but now we have the problem that DLSR are used to make short films, etc. It could be an interesting time to start making a transition. It could be interesting to see what is the diference on modern lenses.
Comment: Thinking about it... It is evry easy to equalize exposures in editing video this days... probably it is not that important now than the film era.
Comment: Color grading is much easier in the digital realm than in the film realm. Even those that now shoot on film can color grade it *after* they've transferred it to digital. There are very few commercial theaters left that can show actual films. Since almost all of the projection systems are now digital, even things shot in film must be digitized to be widely distributed along commercial channels.
Comment: You're also free to use cinema lenses on your dSLR (Canon has range of them, for instance) if you want to, but the increased accuracy in exposure of such lenses comes at a cost (although cinema lenses also feature other expensive features such as reduced focus breathing).
Comment: @szulat I think that's over-precision in the other direction. The nominal f-stop is probably not _precisely_ the aperture number at all (both focal length and f-numbers are often rounded). But even more, knowing that doesn't _really_ tell you anything exact about depth of field; it may give you a general idea, but it depends very much on focal length, print size, subject distance, and so on.
Answer: To add to mattdm's great answer:
In addition to the added exposure precision, which is not important to photography, T-Stops are LESS precise in other ways which ARE important to still photography.
F-stop is the literal proportion of the aperture to focal length. T-stop adjusts this for exposure, but this raw value is important to depth of field. Depth of field won't change when your glass is slightly more or less dim. That makes the T Values a little misleading when calculating depth of field.
To further emphasis how little a difference T-stops make in photography, consider that your frame of reference will be based on other lenses, none of which are perfect, so the difference you will get is not the full difference between the T and F stop values, but the differences in actual T values between lenses. Differences between lenses of similar price, quality, and type will be small.
Answer: F-Stops matter most when you care about knowing your composition and depth of field, T-Stops matter most when you care about knowing your exposure.
Photographers want to control composition first and adjust exposure as needed. Cinematographers need to control exposure first and then compose as needed.
The critical difference with photography is that we can choose any shutter speed we want (within reason) to get the exposure we want.  In cinematography, especially in the old days of film, you had your ISO fixed by the film loaded in the camera and your shutter speed was fixed by the frame rate of the camera** so the aperture (and maybe an ND filter) is the only control you would have over the exposure.  Knowing the T-Stop is critical here or your shots just won't come out right, especially if you're switching lenses to shoot a close-up or a different angle and you don't want the scene to suddenly look brighter or darker after a cut.
In photography you are creating a single image, so control over the composition and depth of field is by far more important than minor relative differences between the actual light transmission between lenses.  You adjust your shutter to compensate and it's not a problem at all.  What you really care about is how your photo is going to look - what is and isn't going to be in focus.  Here the F-stop gives you a more accurate measure.

** Ok, but you could have a shutter speed faster than the framerate to compensate exposure, right?  Yes, but shooting video with a fast shutter at cinema framerates of 24fps ends up producing jarring, stuttery motion that is awful to watch.  A shutter speed near the framerate is needed to produce the natural motion blur that we associate with a pleasing cinema experience.


What is the difference between abstract and interface in php?

Question:
Possible Duplicate:
PHP: What is the difference between an interface and abstract class?

As far as I understand, a class implements or extends abstract or interface class has to use the default methods. I know we can use implement keyword to use multiple interfaces, but we only can extend 1 abstract. Which one to use in real life project and the difference?
Comment: Duplicate: http://stackoverflow.com/questions/1913098/php-what-is-the-difference-between-an-interface-and-abstract-class
Comment: the question could be generalized perhaps... :)
Answer: The differences are both theoretical and practical:

interface is a description of some capability your class has and advertises (so various classes implementing the same interface can be used the same way)
abstract class can be a default implementation, containing the parts which are likely to appear in all the implementations. It doesn't have to implement the complete interface

Example - an interface:
// define what any class implementing this must be capable of
interface IRetrieveData {
    // retrieve the resource
    function fetch($url);

    // get the result of the retrieval (true on success, false otherwise)
    function getOperationResult();

    // what is this class called?
    function getMyClassName();
}

Now we have the set of requirements that will be checked for every class implementing this. Let's make an abstract class and its children:
// define default behavior for the children of this class
abstract class AbstractRetriever implements IRetrieveData {
    protected $result = false;

    // define here, so we don't need to define this in every implementation
    function getResult() {
       return $result;
    }

    // note we're not implementing the other two methods,
    // as this will be very different for each class.
}

class CurlRetriever extends AbstractRetriever {
     function fetch($url) {
         // (setup, config etc...)
         $out = curl_execute();
         $this->result = !(curl_error());
         return $out;
     }
     function getMyClassName() {
         return 'CurlRetriever is my name!';
     }
}

class PhpRetriever extends AbstractRetriever {
     function fetch($url) {
        $out = file_get_contents($url);
        $this->result = ($out !== FALSE);
        return $out;
     }
     function getMyClassName() {
         return 'PhpRetriever';
     }
}

A completely different abstract class (unrelated to the interface), with a subclass which implements our interface:
abstract class AbstractDog {
     function bark() {
         return 'Woof!';
     }
}

class GoldenRetriever extends AbstractDog implements IRetrieveData {
     // this class has a completely different implementation
     // than AbstractRetriever
     // so it doesn't make sense to extend AbstractRetriever
     // however, we need to implement all the methods of the interface
     private $hasFetched = false;

     function getResult() {
         return $this->hasFetched;
     }

     function fetch($url) {
         // (some retrieval code etc...)
         $this->hasFetched = true;
         return $response;
     }
     function getMyClassName() {
         return parent::bark();
     }
}

Now, in other code, we can do this:
function getStuff(IRetrieveData $retriever, $url) {
    $stuff = $retriever->fetch($url);
}

and we don't have to worry which of the retrievers (cURL, PHP, or Golden) will be passed in, and how are they going to accomplish the goal, as all should be capable of behaving similarly. You could do this with an abstract class, too, but then you're restricting yourself based on the classes' ancestor, instead of its capability.
Answer: Multiple vs. single inheritance:

You can only inherit from a single abstract class
You can implement multiple interfaces

Implementation:

An abstract class can actually have functioning code in it.  This lets you share implementation between the child classes
An interface only defines public member functions.  Classes implementing the same interface don't actually share code.

That's what I know off the top of my head.
Answer: The metaphor I heard best was that an abstract class is a half-completed class. It's not done; you still have to finish it. So when you make a class that extends an abstract class, you are just completing what you began in the abstract class. This is also why you can't instantiate an abstract class; that you've made it abstract indicates that it's incomplete. It still needs some additional functionality.
An an interface just guarantees that certain methods, each with a certain number of arguments, must exist within a class that implements it. So that later on, a programmer who uses a class that implements a particular interface can rest assured that they can call certain methods on that class.
Answer: "An Abstract Class can contain default Implementation, where as an
Interface should not contain any implementation at all. "

As far as which to use in real world application... it really comes down to context.
For example, there was a question on here the other day about implementing a game using PHP. Here they had a abstract class defining a monster and any monster could be based off of this abstract class.  This allowed for inheritance of default monster properties.
Whereas for an interface, you are defining a general requirements for a way to "interface" (pardon using the term in the explanation) some system.  An example of this from a recent project I did.  I implemented a soapclient in php to interact with a soapserver from a third party. This interface defines what soap methods the server supports and thus any class implementing my interface must define those methods.
Answer: See this page: 5 Main Difference between Abstract class and Interface in PHP
And this: related StackOverflow answer.
Answer: Here's a good description of the differences between the two:
http://www.supertom.com/code/php_abstracts_and_interfaces.html
It all boils down to the fact that extends is a "is-a" relationship while implements is a "has-a" relationship.


Mining in one years time

Question: In about one years time, when mining is really difficult, what would be the incentive for people to mine?
And if there aren't enough miners, how would transactions succeed?
Answer: Won't happen because of pure greed, if people start leaving difficulty will drop and then it will become profitable again plus even if the normal person can't mine we will have some big company that will profit from mining and keep the network running. This poses other issues when big company's get involved but that's out of scope for this question.
Answer: If they're aren't enough miners then that means that people have lost faith in Bitcoin more than anything. If some miners drop out they will only make mining more profitable for others.

Mining in one years time


How to search for a subject like this

Question: To do a git commit with my own editor (Visual Code)
I needed to setup the editor like this:
git config --global --replace-all core.editor "code -w"

I was searching for this a long time and found out the -w was missing after code.
Without StackOverflow I would probably never know this. Can you explain me a little bit how I can solve such problem. In git config --help or the documentation of git I coulnd't find anything about the -w at the end.
Where did people on StackOverflow found about this?
Answer: The -w is a parameter to VS Code, so you'll not find it in git's help.
You could have found it using code --help or online here
Answer: The issue here is that this -w param is not one from Git but from VS Code.
You can find documentation about it there: https://code.visualstudio.com/docs/editor/command-line
How you could have understood that? If you look at the command, the -w is inside the "" block so it means it is part of the command you pass to the Git config, so a parameter of the VS Code command line tool.

How to search for a subject like this


Hooking after get_header()

Question: Does anyone know a good way to hook just after get_header() without hacking the theme? I know you can hook before the function loads header.php but I am trying to insert some HTML just after get_header() is finished.
Answer: I hate answering questions in the negative because it is easy to go wrong, but there is no core hook that does that-- at least no hook that I have ever seen. I admit it could be handy for a couple of things though.
wp_header() loads the theme's header file. That is about it. It is really just an amped-up include. If you look at the source, there is a hook that runs before the header file is loaded, but not one after.
It is possible that your theme has provided a hook though. I am thinking that that is the only chance you have of this working.
You could do this with Javascript, if that is an option, then you could hook the script to wp_head and wouldn't need to hack the theme. That is, you could load Javascript into the page  using the wp_head hook, and that Javascript could insert your HTML into the page body. It is not a great solution but given your condition about not editing the theme and given that there are no hooks you can rely on across multiple themes, that is the best I can think of.
Comment: +1. `wp_head` is the correct template action to use to add HTML to the document head. If the intent is to add content to the document **body**, then you'll have to wait for Twenty Thirteen, which will include standard template hooks.
Comment: Standard template hooks? I am intrigued.

Hooking after get_header()


Trying to Attach one rigid body simulation with 2 ropes to an jewel (solid object)

Question:

hi the main problem is when i try to use the rigid body simulation the ropes separate from the jewel i want to know if i can activate the rigid body and not separate it from the main model
Comment: Hello, it's a bit vague, does it mean that the ropes are made of a series of bones? Also, what kind of animation are you trying to achieve, etc?
Comment: hi sorry for my bad explanation, im trying to replicate this on the second 0:37 https://www.youtube.com/watch?v=Ix3eh4NpPZc , the ropes are only a single mesh and i added a cube to it (the cube is the soft body) there are 2 ropes so 2 soft bodys and the rope move along the cube, it doesnt have bones, and i can attach the person to only one rope but if i add 2 the bottom part of the 2 ropes separate from each other
Answer: You could do it this way:
Create 3 objects: the 2 ropes object (2 meshes within 1 object) / the cube (your character) / a plane.
Subdivide the plane, give it a Cloth simulation, assign its 2 last vertices to a vertex group that will be the cloth Pin Group, increase the Speed Multiplier value of the simulation if you want the animation to go faster:

Give a Surface Deform modifier to your rope object, with the plane as Target, click on the Bind button:

Select the cube, shift select the rope, switch to Edit mode, select 3 vertices, make the vertices parent with CtrlP:

Play the animation and you'll get that:


If Xerath gets charmed by Ahri in his self-root (R) stance, will he move?

Question: If Xerath uses Rite of the Arcane (R) and Ahri charms him, will he move, or stay in the same spot?
Answer: If Xerath gets foced to move, the ability will be interrupted and he will move. This counts for Ahri charm, fears (Fiddle Q etc.), knockups (Alistar Q etc.) and knockbacks (3rd Riven Q etc.). Normal stuns, roots or silences won't end the Locus but you are unable to cast spells or autoattack while stunned/silenced.
Also if this stance gets interrupted the Bonus movementspeed will not be granted.
There was also a discussion on the forum to make xerath immune to CC that forces him to move, but he's getting a rework now anyways where they replace the W with another spell.
Answer: Lol wiki seems to state that  A champion that roots itself is unable to control its movement and will ignore movement commands (included forced actions, such as fear). A champion that is rooted can still be moved by airborne effects, but it will not break the root.
I will try to test this in the near future
http://leagueoflegends.wikia.com/wiki/Crowd_control
Answer: Xerath wouldn't move, because he is effectively snared or root himself, which prevents movement except for knockups. I believe Riot did this so that you couldn't be snared and pulled it to prevent you to escape, but if you timed them right, it will effectively do it.
Answer: As of Xerath's recent rework the Wiki states:

Interrupting crowd control effects, with the exception of displacement effects, will interrupt Rite of the Arcane and put it on full cooldown.

As Ahri's charm is an interrupting cc effect, it will end Rite of the Arcane and put it on full CD.


What is the difference between Build Solution and Batch Build in Visual Studio 2008?

Question: What is the difference between Build Solution and Batch Build in Visual Studio 2008?
Answer: The key point which seems to be missed in both the existing answers is that batch build allows you to build multiple configurations of each project (e.g. you can build debug and release configurations with a single operation).
With a normal build, you have to use the configuration manager to select just one configuration for each project.
Comment: also, if you have builds for different languages/conditions, batch build lets you build all of them at once.
Answer: in addition to what has been mentioned so far, batch build allows a combination of projects or configurations to be stored as a preset for easier future access.
Answer: Batch build allows you to build any project that you select, and a Solution build only builds the projects that are part of the active solution.
You can customise what projects are part of a solution build by going to menu Tools → Configuration Manager.
Comment: For anyone with VS 2013, it looks like it's under "BUILD->Configuration Manager..." now.
Answer: Another nice thing about batch build is that it lets you build a configuration different than the current one. It is handy for solutions that take a while to switch.
Answer: Building the solution is the same as batch building all projects.  Both methods respect the solution's dependencies.


Is there a way to force Sitecore to sync MongoDB data with it's SQL database?

Question: I am setting up Sitecore xDB and am trying to test exactly what info gets through the system for authenticated and non-authenticated users. I would like to be able to make a change and see the results quickly in Sitecore. I found the setting to lower session lifetime to 1 minute rather than 20. I have not found a way to just force Sitecore to sync with Mongo on demand or at least within 1-5 minutes rather than, what also appears to be about 20 minutes at the moment. Does it exist or is "rebuilding" the database explained here the only existing process?
Comment: please go to http://area51.stackexchange.com/proposals/101710/sitecore?referrer=Fdlyq5_Vj9sZZCwCAPy7-A2 and commit to a dedicated Sitecore Stack Exchange site.  We only need 8 more people with reputation over 200 on another SE site!
Comment: @Reafexus I think Rebuilding the reporting DB will sync data from Mongo to Reporting
Answer: See this blog post by Martina Welander for this and more good info about xDB sessions: https://mhwelander.net/2016/08/24/whats-in-a-session-what-exactly-happens-during-a-session-and-how-does-the-xdb-know-who-you-are/
You just need a utility page that calls System.Web.HttpContext.Current.Session.Abandon(). You may also want to redirect the user to a page that doesn't exist.
Update to address comment
My understanding is that once an xDB session has expired, processing should take place quickly.  In the Sitecore.Analytics.Processing.Services.config file, the BackgroundService agent is set to run on an interval of 15 seconds by default.
You may just be seeing cached reporting data.  Try clearing the cache using the /sitecore/admin/cache.aspx page.  You could also decrease the defaultCacheExpiration setting for the reporting cacheProvider in the Sitecore.Analytics.Reporting.config file.  The default is 10 minutes.
Comment: That link is incredibly helpful overall. But maybe I am asking the wrong question? I want to view all of that information directly in Sitecore. (using the Experience Profile view) THAT page seems to be updated on some delay but I might just be mistaken.


Public Schools and Religion

Question: So today at school (I go to a public high school in Texas) a substitute teacher told a kid to stop saying Jesus Christ. I was wondering if the teacher has the authority to do this? It was clearly for religious motives as the kid wasn't being a distraction or breaking any rules.
Comment: What was the context?  What did the kid say before/after?
Comment: I should've added: The kid saying Jesus Christ wasn't using it because he was religious, it was like "Jesus Christ dude" which the substitute probably viewed as using his name in vain. After the sub told him not to say it he stopped.
Answer: This is a pretty good guide to the student's right to express their views on religion (for or against). For example you may pray in school, but you cannot compel others to listen to your prayers. You may discuss Jesus Christ and you may advocate a religious perspective, if it is on topic (e.g. in a class discussion abortion, but not in an algebra class).
There are familiar ways of saying "Jesus Christ" which would be disruptive, but a general prohibition against uttering a name (on the grounds that the name is of a religious figure) is not a proper application of the separation of church and state -- as the ACLU statement says, SCOTUS did not make public schools religion-free zones. Whether or not the teacher was given the authority to forbid mentioning religious figures by some supervisor, that would not have been proper authorization. Official advocacy of religion in general, or a particular religion, is contrary to the First Amendment, as is official prohibition of religion in general, or a particular religion.
Comment: Yes, assuming consistency with school policy. Hence certain gang-connected shirts can be banned, and there is a policy that does so, but if a teacher had a bizarre belief that purple is an evil color, she could not ban purple clothing in her class. OTOH if people took to wearing purple to annoy the teacher, the school would probably decide that this was disruptive, and ban purple. It really reduces to disruptiveness. I recommend laboring through the Texas Educational Code, all 3032 pages of it.

Public Schools and Religion


Brown Dwarves: Dyson Spheres in disguise?

Question: Would a Dyson sphere make a red dwarf appear to be a Brown Dwarf?  Would it disguise a star enough to misidentify it what size it is?  I'm just wondering if it could be possible that some Dyson spheres are out there drifting around, camouflaged like a rather innocuous and innocent star?
Comment: Disguise it from who? You have an anthropomorphic notion that brown dwarves are useless and not worth investigating. They might be tremendously useful to a space-faring society, all that warm hydrogen, helium and lithium just lying around. Better off building matrioshka spheres as in @SerbanTanasa's answer and lower your radiated energy so nobody sees you from a distance at all.
Comment: I'd expect the emissions to change a lot, be interesting to see what the answers say though.
Comment: What would it look like if it was not a total sphere? Dyson's original idea was based on a continuous evolution of adding more and more satellites to a star. A swarm of independently orbiting industry, solar collectors and living space.
Comment: red dwarf could still have flares
Comment: Disguise it from how far away and from what technology?  The unaided eye (or an IR camera) at 100km can easily distinguish the difference.  At 100 light-years, it's a whole different story...
Comment: @ZanLynx A Dyson swarm would be [detectable like an exoplanetary system](https://en.wikipedia.org/wiki/Methods_of_detecting_exoplanets). If evenly spaced it would only be detected by transit. It would be too regular for a natural formation and practically screams "intelligent life here".
Comment: @Schwern What if it's not intentional?
Comment: A star totally occluded by stuff in orbit: that happens naturally too, and the SETI Seminar I mentioned was about the subtle difference in spectra.
Answer: No, you could not. Temperature probably isn't an issue, but a Dyson sphere shouldn't show the proper spectral lines.
The-best case scenario
This site gives the formula for the temperature of a Dyson Sphere as
$$T=\left( \frac{E}{4 \pi r^2 \eta\sigma} \right)^{\frac{1}{4}}$$
where $E$ is the star's energy output, $r$ is the Dyson Sphere's radius, $\eta$ is the emissivity and $\sigma$ is the Stefan-Boltzmann constant. The Stefan-Boltzmann law says that the energy output (luminosity, $L$) of a star is
$$L=4 \pi \sigma R^2 T_*^4$$
The energy output is $L$, so substituting this into the first expression gives
$$T=\left( \frac{4 \pi \sigma R^2 T_*^4}{4 \pi r^2 \eta\sigma} \right)^{\frac{1}{4}}$$
Which is
$$T=\left( \frac{R^2 T_{\odot}^4}{r^2\eta} \right)^{\frac{1}{4}}$$
$$T=T_*\left( \frac{R^2}{r^2\eta} \right)^{\frac{1}{4}}$$
Wikipedia gives the emissivity of concrete - my Dyson-Sphere-building-material of choice - as $0.91$. Let's say the Dyson Sphere has a radius of $1.5$ times that of the star. That gives me
$$T=T_*(1.5^2 \times 0.91)^{-\frac{1}{4}} \approx 0.836 T_{\odot}$$
Wikipedia and Wikipedia say that a temperature of a red dwarf could be as low as 2300 K, and a brown dwarf could have a temperature of about 1900 K - $0.826$ times the temperature of a red dwarf and so in the acceptable range for our Dyson Sphere.
A more realistic radius
A more commonly-used radius is $r\approx1\text{ AU}$ - the distance from Earth to the Sun. when substituted in, this gives $r=215R$ and $T=0.07T_*$, a much lower value. Interestingly, this fits with previous results. Slysh (1985) looked at things from the perspective of thermodynamic efficiency. The efficiency, $\eta_T$, is given by
$$\eta_T=1-\frac{T}{T_*}$$
It should be expected, at best, that $\eta_T\approx0.95$, so we get $T=0.05T_*$ - pretty close to what our result above was.
As Serban Tanasa rightfully pointed out, there are some problems with concrete. Steel or iron would be a better choice. Their emissivities are given here:
$$
\begin{array}{|c|c|}\hline
\text{Material} & \text{Emissivity}\\\hline
\text{Concrete} & 0.81\\\hline
\text{Cement} & 0.54\\\hline
\text{Galvanized steel} & 0.88\\\hline
\text{Iron} & 0.87\text{-}0.95\\\hline
\end{array}
$$
Note the lower value for concrete than the one I used above. The difference in values turns out to have little effect. At any rate, if we use iron, and choose the lower limit for $\eta$, we get $T=0.071T_*$ - essentially the same as above.
Let's do some recalculations, using both the derivation from scratch and Slysh's results. We'll use a number of stars:
$$
\begin{array}{|c|c|c|c|c|}\hline
\text{Star} & \text{Spectral type} & T_*\text{ (K)} & T\text{ (K)}\text{ (via emissivity)} & T\text{ (K)}\text{ (Slysh)}\\\hline
\text{Zeta Puppis} & \text{O4} & 40000 & 2840 & 2000\\\hline
\text{Eta Aurigae} & \text{B3} & 17200 & 1220 & 860\\\hline
\text{Fomalhaut} & \text{A3} & 8590 & 610 & 430\\\hline
\text{Tau Boötis} & \text{F6} & 6360 & 450 & 320\\\hline
\text{Sun} & \text{G2} & 5770 & 410 & 290\\\hline
\text{Alpha Centauri B} & \text{K1} & 5260 & 370 & 260\\\hline
\text{Gliese 581} & \text{M3} & 3480 & 250 & 170\\\hline
\end{array}
$$
Here, I assume $r=1\text{ AU}$ and $\eta=0.87$.
These temperatures are reasonable values. If we accept a lower temperature limit of $300\text{-}400\text{ K}$ for a brown dwarf, Slysh's rule lets us choose stars roughly as hot as the Sun, or hotter. The emissivity calculations let us choose, in general, any star hotter than a red dwarf.
From a temperature perspective alone, there shouldn't be serious issues.
The spectral line problem
There have been questions as to whether or not the emission spectrum of a Dyson Sphere would match that of a brown dwarf. It is certainly the case that the peak wavelengths would match that of a brown dwarf, with the most light radiated in the infrared. In other words, if you looked at a Dyson Sphere and a brown dwarf with an infrared telescope, you would see two similar sources.
If you measured the emission lines, though, you would definitely see different materials in the two objects - there's no way around that. And yes, the radius of the Dyson Sphere would be much larger than that of a red dwarf - so certainly larger than that of a brown dwarf, as pointed out by JDlugosz.
Here are some lines you'd expect to see in a brown dwarf:

Lithium[1]
Titanium monoxide[2]
Ammonia[2]
Methane[2]
Heavier molecules a la titanium monoxide

Not all of these are necessarily going to be present in a brown dwarf's spectrum, but the absence of all of them in the spectrum of a Dyson sphere is going to raise some red flags. That's you main problem.
Thanks to all those who commented and pointed out inaccuracies and errors; the answer is the better for that.
Answer: No. A Dyson sphere would emit something closely matching black-body radiation. A star, while also emitting something close to black-body radiation, has tell-tale spikes in its spectrum. Below is the sun's spectrum compared to what its ideal black-body spectrum would look like:

Brown and red dwarfs have their own "fingerprint" signatures, which differ from that of both the sun and an ideal black body. This fingerprint is the first thing astronomers look at, so I would not expect them to be fooled for long.
Comment: @bowlturner easy to fake; just don't.  Have a cloud of dust around your engineered stuff, and distant observers will see only a dust cloud in thermal equilibrium with the energynfrom the sun. That it got used for energy and changed to different frequency doesn't matter as long as it's still absorbed by the dust. For extra stealth, make sure the composition of the cloud is natural, not your tailings and trash.
Comment: So how hard would it be to emit enough energy to in the right wave lengths to fake out distance observers?
Comment: @bowlturner, it's conceivable to do so. He who can build a Dyson Sphere could also build an ACME "Spectral Shaper Pro". But then again ckersch's issues of wrong mass apply.
Comment: cool, hadn't even thought of emission absorbtion bands!
Answer: I don't think so, because a dyson sphere would not have the same emission spectrum of a star.
Consider two cases: we can have a translucent dyson sphere that lets out some of the light of the star, or we can have a dyson sphere that is opaque and emits light as blackbody radiation due to being heated by the star.
The light initially emitted by the star will have an emission spectrum that is dependent on its temperature. Elements which are either fully ionized in a star or which are too cold to absorb energy will not absorb light. Based on this, we can identify the temperature of a star, not based on its luminosity, but based on its emission spectrum.
Now consider the light emitted by the dyson sphere. If we emit as a black body, we will not have the same emission spectrum as our star unless the dyson sphere has the same elemental makeup as the star in question. Since stars are made up mostly of gasses, this would be difficult to achieve. If we emit through transparency, we will still have the same emission spectrum as a red dwarf, but appear less luminous. Most materials also have a transparency that varies based on spectrum, so we'll see the spectrum of the red dwarf reduced at different frequencies dependent on the material of the sphere.
A search for Dyson spheres has actually been carried out under a similar theoretical framework. Under the assumption that most terrestrial objects radiate mostly in the infrared spectrum, astronomers searched for stars that had a spectrum shifted more towards that part of the spectrum than the star would otherwise be expected to emit under. The search did not successfully find anything that looked like even a partial Dyson sphere.
Even if we manage to get our Dyson sphere to emit the same spectrum of a brown dwarf, though, it will still appear too big and too massive to be a brown dwarf. Brown dwarves are smaller than red dwarves, and a Dyson sphere would need to be significantly bigger than a red dwarf.
Comment: How do you know how big or far away it is if there isn't near another star to compare it too?  all of our classifications are based on assumptions of other measurements.
Comment: @RBarryYoung paralex works up to 20k lightyears; still within our galaxy.  Red shift of local group galaxies won't show Hubble's relationship (Andramada is heading right for us and is blue shifted), so takes effect at much larger scales than millions of light years.  An important mechanism you didn't mention is Cepheid variables. Trying to find the spelling for that I came upon a great diagram: http://en.m.wikipedia.org/wiki/Cosmic_distance_ladder
Comment: Depends how far it is. If it's very far away, redshift can be used to assess size. For closer stars, parallax. If nobody looks to closely at the star, it may well go unnoticed, but under close observation I would expect that the Dyson sphere would look noticeably different.
Comment: IIRC, there's a lot of gap between parallax limits (few hundred LY, I think), and the beginning of effective redshift (has to be at least outside our own galaxy, so tens of thousands of LY).
Comment: It would emit in infrared, probably moreso than a regular star in the case of a partial Dyson sphere. This is because a partial Dyson sphere would absorb energy and emit blackbody radiation, which would be mostly infrared if the Dyson sphere was around the same temperature of earth. For a hotter Dyson sphere, the blackbody radiation would be dominated by higher energy wavelengths. Either way, the emission spectrum of the Dyson sphere would lack the absorption spectra of the stellar atmosphere.
Comment: What would the spectrum of a Dyson Sphere be, then? Why wouldn't it emit in the infrared?
Comment: @ckersch Okay, cool. Makes sense. How would that differ from a brown dwarf, which also heavily radiates in the infrared?
Comment: Assuming they're the same temperature, the atmosphere of the brown dwarf would absorb certain wavelengths of light based on its temperature and the composition of its atmosphere. The Dyson sphere's spectrum would be continuous. This page gives a decent description of absorption spectra in stars: http://earthguide.ucsd.edu/eoc/teachers/t_universe/p_spectra.html
Comment: If an alien civilization were interested in disguising their Dyson spheres, would it be possible to build one with a small radius so the gravity from the star would be enough to support a hydrogen/helium atmosphere around it, one which would give the same absorption lines as a brown dwarf? I suppose it would have to be a thick enough atmosphere so that a significant proportion of the blackbody photons emitted by the shell would be absorbed and re-emitted by the gas molecules, perhaps that wouldn't work without an extremely thick gas-giant-like atmosphere.
Comment: @jdlugosz Ah, thanks for the reference.  The goalposts have apparently moved quite a lot since I was last up to date on this..
Comment: Even if an alien civilization could build a Dyson sphere with exactly the same emission spectrum as a brown dwarf, it would only look like a brown dwarf to races that didn't have the technology to take a close look at said star. Closer inspection would still reveal a star with no sunspots and no flare activity. Yes, you could hide from modern humans, but the sphere would be obviously aberrant to the telescopes we're likely to have even 50 years from now. It would also be far easier to just build a cold dyson sphere that wouldn't show up on telescopes.
Answer: Not an expert on blackbody radiation, so you might get a more competent answer on (Astro)Physics, but conceptually if you have a matrioshka system, where each layer captures and uses the radiation of the more inward layer, you can bring the blackbody radiation level down to an arbitrarily low level >= CMB.
The only "disguise" issue would be that brown dwarfs are generally capped around $80 M_J$ (Jupiter Masses), while red dwarfs are generally at $[0.1-0.5] M_S =[100-500]M_J$. There might be a small overlap at the lowest of the low red dwarfs. But generally, your apparent stellar radii might mismatch, and the orbits of any remaining planets would be anomalous, upon closer inspection.
Comment: So it could be a great disguise unless someone is actually looking for you!
Comment: @HDE226868 right, but that is assuming nothing like a Dyson Sphere is altering it's luminosity.  We'd likely mistake it's distance from us right?  I suspect a serious study and tracking of one of these would show up irregularities, but first someone would have to care, and there are a lot of brown dwarfs out there.
Comment: But don't we compute the masses by the radiation put out?
Comment: Hmm. See http://physics.stackexchange.com/questions/141875/how-do-you-estimate-the-mass-of-a-star
Comment: Reading that answer basically told me that a star by it's lonesome is mostly guessed at by it's radiation.  So if it looks like a brown dwarf, we classify it as such...?
Comment: Looks like it. Unless we have a reason to bother estimating its mass by the orbits of gas giants in orbit (or found it suspicious that there are no gas  giants in orbit). Which we might if we had a reason to look for Dyson spheres...
Comment: @bowlturner You can use the mass-luminosity relation to figure out a star's mass based on its luminosity.
Comment: @bowlturner  s/it's/its/g
Comment: @jdlugosz  some days are better than others...
Comment: @bowlturner agreed.
Comment: @jdlugosz You're our site's grammar guru.
Comment: @HDE226868 That's how I get my points: one at a time for edits :) *"it is"* has become a pet peeve, probably as a side effect of drilling (always mentally expand the contraction) so *I* get it right. I have been a magazine editor, BTW. Chorus all: *it's is it is; his/hers/its are a matching set.*
Comment: @jdlugosz Ha, I've gotten loads of points on Physics and Math for editing LaTeX. Ya, I get pretty annoyed when I see people confusing *its* and *it's*, though *I couldn't care less* $\to$ *I could care less* is also up there on my list.
Comment: @SerbanTanasa so where does the energy go? Won't it still produce the same temperature at the final radiating surface, no matter how you used the differential between the hot star and cold space to do useful work?
Comment: @HDE226868 you and Harlan Ellison. I (among a few in a group) managed to enrage Stan Kelly-Bootle (now recently departed) over *whose*. Now eye get that write to. :)
Answer: First - Brown Dwarfs are small.  A Dyson Sphere for our Solar System to duplicate Earth like environments would have to be about 2 AU in diameter to give Earth-like solar radiation incoming.  A Dyson Sphere would be BIG.
The mass of the Dyson Sphere would be large - the sun itself and the mass of the sphere - so in a double star would look very different than a light brown dwarf.
The Dyson Sphere, in the end, would have to re-radiate all the incoming solar energy out the shell as heat. So the total luminosity would be the equivalent of the star inside, not the small amount reported.  If you trapped heat in, you bake your sphere until it glows on its own.
EDIT:
I just thought of another test. A Dyson sphere, due to its large size, will rotate very slowly if at all. A planet or sun rotates about its axis in hours or days. This speed difference between the limbs of the object give splits to the spectral lines that can be seen.  So a visible Dyson sphere would look anomalous due to its slow rotation.  I'd think that to get a sphere to revolve about its axis in months or less would require unreasonably strong materials.
Comment: A red dwarf is much smaller than our sun.
Comment: True enough...but a Dyson Sphere still has to have the diameter of the habitable zone orbit of said star...which is much larger than the diameter of a normal star.
Comment: @bowlturner, such Dyson Disguise is going to be *enormously large brown dwarf* just because radius of "successful" low-mass star is bigger than "failed" one's.
Answer: Look on YouTube for the weekly SETI seminars. Not too long ago they discussed exactly that, and what instruments are needed to be able to tell if that were the case!
I seem to recall that it's not brown dwarfs that it looks like (a brown dwarf is only just larger than Jupiter) but some types of dusty systems or star formation. Models of spectra show that a particular spectral band that is not distinguished in current readings would show the difference between Dyson spheres and imposters.
Answer: Most of the answers above assume a shell of material located at a radius around a star which would support Earth-like habitats. However, colonization by robotic life would produce a significantly different architecture. And, the other respondents assume that a dyson sphere (or Dyson swarm, rather) would be orbiting a luminous star - if, instead, a swarm was harvesting material from a Jupiter, it may be dim enough to go unnoticed. If I was a space-faring artificial life form, I would prefer to orbit and mine a Jupiter - lower gravity would make siphoning gas much simpler, and there is no risk of a nova (with a star, loss of gasses would lead to cessation of fusion at its core, followed by collapse, then explosion as fusion re-ignites...). We do not have the sophistication to detect cool, wayward Jupiters, so this possibility may fit your goal of a 'hidden Dyson'. For example, the recently discovered super-magnetic Jupiter: https://phys.org/news/2018-08-vla-extrasolar-planetary-mass-magnetic-powerhouse.html


Why don't I get an email when my question is put on hold?

Question: I get email notifications when someone answers or comments on one of my questions, but not when one of my questions is put on hold.  That's an event I'd like to know about!  Why am I not notified?
Comment: It's probably to reduce the amount of whining.
Comment: Btw the question you asked that sparked this would probably have been better asked on http://unix.stackexchange.com.
Comment: So now you're not only ignoring differences, but deleting comments about them?  I guess I won't be notified when you delete this comment either.
Answer: You only get email notifications for things that send you SE notifications... and question closure is not one of them.
Jeff Atwood had posted a (heavily downvoted) answer there which seems to have gotten deleted, but the gist of his reasoning was that it would a) increase complaining b) be too many inbox notifications. No-one really liked his reasoning though.


Is there anything that will remind me that my laptop is in High Performance mode?

Question: I sometimes turn on High Performance mode on my Windows laptop so games run smoothly. However, too often I forget to turn it off, sometimes for weeks, and assume my battery's being drained by Chrome, low reception, or some other factor. Is there any utility that'll let me get a popup reminder, say, 5 hours after I turn it on?
Answer: You can give it a try this software is called BatteryCare It monitors the battery's discharge cycles and helps increasing it's autonomy and improving its lifetime.
http://batterycare.net/en/index.html
From the Website:

Features

Battery's discharge cycles monitoring
  The advanced algorithm accurately records when a complete discharge cycle is performed.
  When the configured number of discharge cycles is reached, a notification balloon pops up to remind that a full discharge is required.
Complete battery information
  It calculates the statistical remaining time in laptops that don't support the battery time left information and only list the charge percentage.
  Shows all the detailed information about the battery, such as wear level, capacities, consumption, manufacturer, etc.
CPU and HDD temperature reading
  BatteryCare constantly monitors your CPU and hard drive temperature, either in degrees Celsius or Fahrenheit.
Automatic power plans switching
  Depending on the power source of the computer, BatteryCare can automatically select the power plan you prefer.
Control over Windows Aero and demanding Services
  Automatically disable the graphics accelerated theme in Windows Vista and/or demanding services that degrade battery lifetime.
  Once the laptop stops running on batteries, the theme is re-enabled and the stopped services are restored.
Notification area information
  It features a compact popup with the essential information you need to quickly monitor. Temperatures, charge status, remaining time and power plans
Auto-updates
  No need to trouble in downloading new installers, when a new version is available, the program updates itself.
Lightweight in the system
Comment: 'I've just edited the post to make it better readable, highlighting the OPs "wished feature" by making it bold. Not exactly what he asked for, but pretty close at least. If there's no solution for a "popup", a reminder in the notifications certainly is the next best thing. Thanks for providing the additional details!
Comment: hope I have answered clearly but as you mentioned im still doubtful with my answer!based on this feature Notification area information
It features a compact popup with the essential information you need to quickly monitor. Temperatures, charge status, remaining time and power plans,Im comfortable to post this answer
Comment: You welcome :) !
Comment: I just installed it, and it has the option to change the power plan when plugged in or unplugged, but not notify me of a power plan. That'll work for me, so +1, but it doesn't answer the question, so I'd feel wrong accepting it as an answer.


Eph. 2:6 and raised us up together, and made us sit together in the heavenly places in Christ Jesus

Question: We know that Jesus is sitting at the right hand of God.
In Eph.2:6 it says that we, believers of Christ, made us sit together in the heavenly places in Christ Jesus. Does it mean we are also sitting where Christ is seated?
What is " sit together in the heavenly places in Christ Jesus" really mean?
Comment: Good question. Up-voted +1. By baptism, we are dead with Christ and Paul says 'I am crucified with Christ'. This text follows on from those experiences.
Comment: @Giselle This might help. I'm paraphrasing Revelation 20:6 here: "Blessed and holy is the one who has a part in the first resurrection [baptism into Christ]; over these [Christians], the second death [spiritual death] has no power, but they [Christians] will be priests of God and of Christ [all Christians are priests and royalty: 1 Peter 2:9] and *will reign with Him for a 1,000 years* [until Christ's return]." In Christ, we are reigning with Him now. We were dead to God before our death, burial, and resurrection through baptism. The 1,000 years is symbolic of the amount of time until the end.
Answer: Ephesians 1:3
English Standard Version

Blessed be the God and Father of our Lord Jesus Christ, who has blessed us in Christ with every spiritual blessing in the heavenly places,

heavenly realms.
ἐπουρανίοις (epouraniois)
Adjective - Dative Neuter Plural
Strong's 2032: From epi and ouranos; above the sky.
The Greek word, by itself, does not carry a sense of precise location.
Ephesians 2:6
English Standard Version

and raised us up with him and seated us with him in the heavenly places in Christ Jesus,

New International Version

And God raised us up with Christ and seated us with him in the heavenly realms in Christ Jesus,

Does it mean we are also sitting where Christ is seated?
No, not necessarily. Pulpit explains:

As God placed Jesus at his right hand in heaven, so he has placed his people with him in heavenly places; i.e. places where the privileges of heaven are dispensed, where the air of heaven is breathed
Comment: Some translate the word as 'the heavenlies'. See [The Englishman's Greek New Testament](https://archive.org/details/englishmansgreek00step/page/502/mode/2up).
Answer: EPH 2:6 And hath raised us up together, and made us sit together in heavenly places in Christ Jesus:
The word translated "together" (synegeirō) here was used three times - here in Ephesians, and also in Colossians.
COL 2:12 Buried with him in baptism, wherein also ye are risen with him
COL 3:1If ye then be risen with Christ
It is describing our union with Christ in being "quickened" (Ephesians 2:5), "raised" (this verse), and seated "in heavenly places" (this verse). None of these things are possible on our own. It is only through our union with Christ that any of this is attainable.
Made us "sit" (sygkathizō), used in this verse, "raised" (Ephesians 1:20 and this verse), and "quickened" (Ephesians 2:1 and 5) are all in the aorist tense. This indicates something that God has already accomplished in Christ, not something that is off in the future.
So this verse (Ephesians 2:6) is a present reality for believers. To understand what this means will be determined somewhat by your doctrinal foundation. Especially on your understanding of the 'spiritual' aspect of Christianity. And here 'views' differ.
Nevertheless the reality of what these verses are clearly stating can not be ignored.
Answer: Here are some possibly relevant "sitting" passages. It seems clear to me that at a minimum, Paul would have us understand that we are being given an incredibly privileged and honored position with Christ. Based on other passages, some measure of co-regency or co-judging seems also be implied.
Ex. 11:5

the firstborn of the Pharaoh who sits on his throne

(Pharaoh letting his firstborn sit on his throne as co-regent? cf. Ex. 12:29)
Ruth 4:1-2 -leaders of Bethlehem sit down together to decide an important matter
1 Sam. 2:8

He lifts the needy from the garbage heap To seat them with nobles, And
He gives them a seat of honor

1 Kings 2:19

the king stood to meet her, bowed to her, and sat on his throne; then
he had a throne set up for the king's mother, and she sat on his right

(cf. Neh. 2:6 where Artaxerxes' wife sat next to him)
Job 36:7

He does not withdraw His eyes from the righteous, But with kings on
the throne He has seated them forever, and they are exalted

Ps. 61:6-7

You will prolong the king's life; His years will be like generations.
He will sit enthroned before God forever;

Ps. 110:1

The Lord says to my Lord: "Sit at My right hand...

(cf. Matt. 22:44)
Ps. 113:7-8

He lifts the needy from the garbage heap, To seat them with
noblemen...

Pr. 31:23

Her husband is known in the gates, When he sits among the elders of
the land

Matt. 19:28

you who have followed Me, in the regeneration when the Son of Man will
sit on His glorious throne, you also shall sit upon twelve thrones,
judging the twelve tribes of Israel

Matt. 20:21

Say that in Your kingdom these two sons of mine shall sit, one at Your
right, and one at Your left

Luke 22:69

the Son of Man will be seated at the right hand of the power of God

Rev. 3:21

The one who overcomes, I will grant to him to sit with Me on My
throne, as I also overcame and sat with My Father on His throne

Rev. 20:4

Then I saw thrones, and they sat on them, and judgment was given to
them. And I saw the souls of those who had been beheaded because of
their testimony of Jesus and because of the word of God, and those who
had not worshiped the beast or his image, and had not received the
mark on their foreheads and on their hands; and they came to life and
reigned with Christ for a thousand years


Moving Rooms in Boss Monster

Question: If a card tells you to swap the placement of two rooms in any dungeon  and you have multiple rooms on top of each other do you swap the placement of just the room on top of the stack or do you move the whole stack of rooms?
Answer: For the purposes of moving rooms, a room is made up of every card in the stack at each of the five positions in your dungeon.
So when a card tells you to move a room, you move every card in that stack.
From the FAQs & Advanced Rules section of the rulebook (page 19):

When an effect allows you to swap the placement of
  Rooms in a dungeon, how do you deal with Rooms
  built on top of other Rooms?
You can rearrange any stacks of Rooms, but you
  cannot change the order of Rooms within each stack.
  The visible Rooms do not change.

Moving Rooms in Boss Monster


Performing rights on a cruise ship

Question: I've worked for many years on a cruise ship performing my own songs, and I'd like to know how to claim the royalties. I'm a GEMA member and of course, I have reported to them. they said that sent the claim to SIAE in Italy as the ship's flag is Italian. It has been already 6 years and GEMA seems to know be able to solve it and they told me that they aren't sure how it works with the cruise ship industry. Someone here with the same experience? Thank you
Comment: Assuming you got paid for the performances by the cruise lines, what are the royalties for?
Comment: @Moo royalties to the songwriter for songs performed are separate and in addition to whatever is paid to the performer(s) for the performance; these are separate rights with separate (and quite different) remuneration process. There's little practical distinction between the cases where the performer(s) play songs by other songwriters (which is common) and when they play songs where the songwriter is one of the performers. Also, if a band is "playing their own songs", songwriting rights affect how the money is distributed between different members of the band.
Comment: @Peteris given the performer is picking their own songs to perform, why isnt that covered under the original payment?
Comment: Hi, Yes, what I mean is that. I've been performing my own songs. And they are also in the playlist on my contracts.
Answer: The law on a ship is complicated

While you were in any inland waterway (i.e. in the harbor), local law applies.
Similarly, while you were in the territorial waters of a nation (usually 12 nautical miles from the coast but the Mediterranean is complicated), local law applies.
A nation has jurisdiction in its contiguous zone (12-24 nautical miles, again the Mediterranean is complicated).
On the high seas, the jurisdiction is the flag of the ship.

You would need to know where the ship was for each of your performances and claim from the copyright royalty organization (through the German one), for each relevant country.
However, your contract with the cruise line may spell out something different.
Comment: Hi, Dale thanks for your answer. As the flag of the ship is Italy, I claimed the royalties of my songs to the SIAE, and it seems that after 6 years they don't bother to solve or answer me. I keep calling and sending emails and they say that it's complicated but never solve anything. The cruise ships make everything possible to get rid of royalties payments and it seems that nobody is doing anything to change that scenario.
Comment: @SantiagoFerreira get your lawyer to send them a letter - getting the law involved can probably not action.

Performing rights on a cruise ship


Python Script using pandas to plot histograms between the features

Question: I am working around with data from Kaggle : Titanic Competition dataset.
Script
#cols : List of all column header
cols = list(df.columns.values)
#script to plot histograms of all columns with respect to column: "Survived"
for val in cols:
       df.groupby('Survived')[val].hist(alpha = 0.2)

Code of importance (COI)
df.groupby('Survived')['Age'].hist(alpha = 0.3)

Output

The COI works but the Script is not working. The script will help to plot all the histograms in one go without manually inserting the column in the COI.

The script is running indefinetly.
The COI also runs indefinetly but once I execute the following code:

df.groupby('Survived').Age.hist(alpha = 0.2) #This runs flawlessly

COI runs perfectly. (Not able to figure out why).

The scripts are written in Kaggel Kernel.

Given the above details, please help me figure out a way to achieve the above script either by making improvements to the Script or an alternate way of doing the same.
Comment: Add plt.show() after that line
Comment: I meant use seaborn or something like that for the plot and then add explicitly that
Answer: cols = list(df.columns.values)
for val in cols:
        df.groupby('Survived')[val].hist(alpha = 0.2)
        plt.show()

just add plt.show() in the end it would create histogram for all columns


New pump, same problems

Question: Saturday my father and I replaced our well pump as it had gone bad earlier in the week as well as the pressure switch. Today we lost water again. We have a 3/4 hp well pump as well as a 40/60 pressure switch. For some reason the pressure won't go above 40 psi. Any ideas on what could be the issue and what a solution might be? Thanks in advance.
Comment: Pipe leaking or low water level in the well.
Comment: Or bad pressure switch.
Answer: how did you know the pump and pressure switch "went bad".   Most likely is that the production amount  of the well  took a turn for the worse and the pump was "sucking air" .  Solution:  Get a well guy out there with measuring electrodes to determine the static water level (IE w/o the pump running) and then then the water level after it's been running for a while.  Then compare to the depth of the pump and figure out if  the well production isn't good enough.  2 fixes:  install depth measuring equipment to turn off the pump when the water level gets too low or reduce the size of the pump to match the capacity of the well.

New pump, same problems


Is it true that having the Nexus S is much better as an Android developer?

Question: Soon, I'll be starting Android development, as I know a bit of Java. I'll also be getting an Android phone. My two options are the Nexus S and the Atrix 4G. I've heard the Nexus series is ideal for developers - can someone tell me why? Why is getting the Atrix bad as a developer?
Comment: I didn't understand the downvoting for this question. For some who did that, please clarify
Comment: IMO, Stackexchange users should be require to give a brief description of why they downvoted a thread
Answer: The Nexus S could be considered "better" for two main reasons:

It features only standard Android software, nothing custom from the manufacturer or carrier, and
It gets updated faster than other handsets (because the updates come directly from Google, whereas other phones need to wait for the manufacturer to release the update and sometimes the carriers delay updates even further).

On the other hand, the Atrix has a faster processor (dual core, the Nexus S is only single core and basically just a slightly modified Galaxy S), better display and (IMO) looks better, too :-)
Answer: I'd go for a slower handset - pref the current most popular rather than the best to develop on.  The majority of your users aren't going to be using the latest and greatest so if you are developing anything which pushes your dev handset to the limit, and you have a great handset, chances are that a lot of your users won't be able to use your application.
I've encountered handset specific issues with Android programs I've written in the past, so it's probably a good idea to make sure this doesn't happen to the handset most likely to be used by the people who want to download your app.
To be honest, I'd get multiple handsets (2nd hand off ebay - don't bother buying new) - work out what range of handsets (in terms of performance and screen size) you want to support and try and get a handset near the bottom of that range, one near the middle and one near the top - if you do this and get different screen sizes that should cover your bases.  I prefer this method to relying too much on the emulator as it'll let you play with the app on the different handset speeds and screen sizes and it'll give you much better hands on experience than the emulator can.
Answer: if your development require you to support the latest released android OS version
fast updtes to the OS is the main reason you should consider nexus  phones