Tried installing it from command line (sudo apt-get install gwget)  and I get this:  Reading package lists... Done Building dependency tree        Reading state information... Done Package gwget is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'gwget' has no installation candidate   what does it mean?  I'm using Ubuntu 13.10
What does the above Error mean? What is an installation candidate?  I was trying to do  sudo apt-get install munin-memcached     and I get this message:  Reading package lists... Done Building dependency tree        Reading state information... Done Package munin-memcached is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source E: Package munin-memcached has no installation candidate   I googled for the problem and someone said to do a apt-get upgrade but it still did not solve my problem.
Link to the recommended job is broken in the mobile apps The link to the recommended job in the app brings you to a page with the text: Not Found    Looking at the link it seems like after changing the URL structure in Stack Overflow Jobs they have not been updated in the apps.  For the job in the screenshot this is the used URL in the app:    The correct URL is: How many triples $(x,y,n)$ are there such that $x^n - y^n = 2^{100}$ What is wrong with using inline functions? While it would be very convenient to use inline functions at some situations,  Are there any drawbacks with inline functions?  Conclusion:  Apparently, There is nothing wrong with using inline functions.  But it is worth noting the following points!   Overuse of inlining can actually make programs slower. Depending on a function's size, inlining it can cause the code size to increase or decrease. Inlining a very small accessor function will usually decrease code size while inlining a very large function can dramatically increase code size. On modern processors smaller code usually runs faster due to better use of the instruction cache.  The speed benefits of inline functions tend to diminish as the function grows in size. At some point the overhead of the function call becomes small compared to the execution of the function body, and the benefit is lost  There are few situations where an inline function may not work:   For a function returning values; if a return statement exists. For a function not returning any values; if a loop, switch or goto statement exists.  If a function is recursive.   The __inline keyword causes a function to be inlined only if you specify the optimize option. If optimize is specified, whether or not __inline is honored depends on the setting of the inline optimizer option. By default, the inline option is in effect whenever the optimizer is run. If you specify optimize , you must also specify the noinline option if you want the __inline keyword to be ignored. "a" or "an" in front of a word beginning with a vowel I was writing a text when I came to say 'a union', then it struck me that I need to change the 'a' to 'an'. But for some reason, 'an union' didn't sound right.   Why doesn't it work? Is it because its a mass noun, instead of a regular noun? Downloading files using wget I am trying to download files from .  The URL is:   When I use this command:  wget http://www.ncbi.nlm.nih.gov/geo/download/?acc=GSE48191&amp;format=file    I get only index.html?acc=GSE48191 which is some kind of binary format.  How can I download the files from this HTTP site? A 'for' loop to iterate over an enum in Java What causes javac to issue the "uses unchecked or unsafe operations" warning For example:  javac Foo.java Note: Foo.java uses unchecked or unsafe operations. Note: Recompile with -Xlint:unchecked for details. Implement ```-style (fenced) Markdown code blocks Currently, Stack Exchange’s Markdown parser only allows four-space indents to represent code blocks:      // some code     // another line of code    and other Markdown implementations allow for an alternative syntax, that doesn’t require indenting each code line:  ``` // some code // another line of code ```   This is much more convenient to type out. It would be super useful if Stack Exchange could support this syntax.    By extension, this syntax also allow you to specify the source language right after the opening ```:  ```js // some code // another line of code ```   …which would then enable syntax highlighting for that specific language. Although it’s interesting metadata, I don’t think this feature is needed on Stack Overflow, as the syntax highlighting library works pretty well for various languages.  So, even if you would allow this syntax but ignore the ```language, this would greatly improve my productivity on Stack Exchange.  What do you think?  The moderators are currently collecting feedback regarding this feature, so please post a comment with your thoughts. Good idea? Bad idea? Don’t really care? What do you think are the benefits/drawbacks? Experiences? Let them know! Thanks! How can I use docker without sudo? On Docker's documentation pages, all example commands are shown without sudo, like this one:  docker ps   On Ubuntu, the binary is called docker.io. It also does not work without sudo:  sudo docker.io ps   How can I configure Docker so that I don't need to prefix every Docker command with sudo? Why is glass transparent? I upgraded my Mega Ring and have been looking for Mega Stones, and I found . However, the Mega Stone isn't in the place it's supposed to be, and I'm sure the location is right. Why isn't my Mega Stone here? Test condition in if command Any idea why echo statement is being executed in both scenarios?  Outputs it worked:  #!/bin/bash  rizwan='' if [ -n $rizwan ]; then   echo "it worked" fi   Replace -n with -z, and it outputs it worked when expecting no output:  #!/bin/bash  rizwan='' if [ -z $rizwan ]; then   echo "it worked" fi How can I disable cloud-init? I have a fully-configured instance and an image from that for an autoscaling group. When autoscaling new instances from this image, it calls cloud-init. cloud-init changes the hostname and breaks fstab.  I want to prevent cloud-init from starting on instance launch. How does one go about proving that the function $x \sin x$ is not uniformly continuous on the set of real numbers ?  Any method that uses the sequential criterion for discontinuity would be preferred.  Thanks in advance ! When traveling to a country with a different currency, how should you take your money? I am trying to make a callout to AWS S3 using named credentials and Apex  The named credential is set up as follows  Label: AWS S3 Name: AWS_S3 URL: https://bucket-name.s3.amazonaws.com - Certificate: Identity Type: Named Principal Authentication Protocol: AWS Signature Version 4 AWS Access Key: AKIAxxxxxx AWS Secret Access Key: xxxxxx AWS Region: ap-southeast-2 AWS Service: s3 - Generate Authorization header: true Merge fields in header: false Merge fields in body: false   The Apex class is very simple  HttpRequest req = new HttpRequest(); req.setEndpoint('callout:AWS_S3'); req.setMethod('GET');                        Http http = new Http(); HTTPResponse res = http.send(req);                 System.debug(res.getBody()); return res.getBody();   The response body contains the following:     SignatureDoesNotMatchThe request signature we calculated does not match the signature you provided. Check your key and signing method.AKIAxxxxx   I have used the same bucket, endpoint and credentials using Postman and am able to successfully return the list of objects in the bucket so it is not an IAM permissions issue  There have been a couple of similar questions on stackexchange but unfortunately they do not provide any resolution or assistance in this case:    I've tried looking for code samples or further pointers in the Apex documentation but it doesn't really give any further guidance on how to proceed or correctly set this up so I'm a bit stuck Say there are $m+n$ elements split into two groups ($m$ and $n$). The variance of the first group is $\sigma_m^2$ and the variance of the second group is $\sigma^2_n$. The elements themselves are assumed to be unknown but I know the means $\mu_m$ and $\mu_n$.  Is there a way to calculate the combined variance $\sigma^2_{(m+n)}$?   The variance doesn't have to be unbiased so denominator is $(m+n)$ and not $(m+n-1)$. Why doesn't the T-800 run? I just re-watched the first two films in the Terminator series. The T1000 (Robert Patrick) does a lot of running, and is quite fast.  I didn't see many scenes where the T800 (Arnie) ran. Is it because he's really heavy? Is he mainly designed as a heavy "stand your ground" machine?  The only scene I could see him running is in T2 in the mental hostpital where the T1000 morphs through the metal gate and his gun gets caught. Then the T800 does a little jog to get into the elevator following John and Sarah. (anybody know of any other running/jogging scenes?) (EDIT Arnie also breaks into a run while pursuing Reece and Sarah down the alley after the NOIR nightclub attack.)  If he can at least jog though, why wouldn't he do this throughout the entire film? You would think that from a "chance of survival" point of view, if he could get a John even the slightest bit faster then he'd do so.  Of course, maybe I am overthinking this... Arnie walking around slowly is a lot more badass than Arnie jogging around.  Edit: Just watched T3 again, the T800 also ran towards the end when the big hangar door was closing and he ran over to slow it down. Interested in other examples of the T800 running too. I don't understand an answer. Should I add a comment, or post a new question? I recently (today) asked a question that received what seems to be a clear, concise answer, but one that's beyond my ability to understand (I'm at the cut-and-paste stage with JavaScript, and the answer seems to assume more knowledge than I actually have).  Is it considered better to ask follow-up questions as comments to the answer given, or should I post "fresh" questions to Stack to help me understand the answer that's been given? MonoTouch.Dialog: How to set limit of number of characters for EntryElement