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Assume that I have a set of data pair where index 0 is the value and index 1 is the type:
6 Answers
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How to detect if JavaScript is disabled?
...ection. As an alternative it is possible to set a cookie using JavaScript, and then test for that cookie using server-side scripting upon subsequent page views. However this would not be suitable for deciding what content to deliver as it would not be able to distinguish visitors without the cookie...
Can't find the 'libpq-fe.h header when trying to install pg gem
...nx), 11.10 (Oneiric Ocelot), 12.04 (Precise Pangolin), 14.04 (Trusty Tahr) and 18.04 (Bionic Beaver)):
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/usr/include/postgresql/libpq-fe.h
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So try installing libpq-dev or its equivalent for your OS:
For Ubuntu/Debian systems: sudo apt-get install libpq-dev
On Red Hat Linux (RHEL) systems:...
How to check if running in Cygwin, Mac or Linux?
I have a shell script that is used both on Windows/Cygwin and Mac and Linux. It needs slightly different variables for each versions.
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What is a StoryBoard ID and how can i use this?
i'm new to IOS developing and recently started in Xcode 4.5. I saw for every viewController that i could set some identity variables including the storyboard ID. What is this and how can i use it?
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What is “:-!!” in C code?
... effect, a way to check whether the expression e can be evaluated to be 0, and if not, to fail the build.
The macro is somewhat misnamed; it should be something more like BUILD_BUG_OR_ZERO, rather than ...ON_ZERO. (There have been occasional discussions about whether this is a confusing name.)
You...
use localStorage across subdomains
...on browsers that can support it (anyone but IE). The problem is site.com and www . site.com store their own separate localStorage objects. I believe www is considered a subdomain (a stupid decision if you ask me). If a user was originally on site.com and decides to type in www . site.com on ...
Can Android do peer-to-peer ad-hoc networking?
Is it possible to set up Android in ad-hoc peer-to-peer wifi mode? For example, I would like to have one phone broadcast a message, and have all peers in the network receive the broadcast, without having a server. I would like to use wifi since bluetooth range is more limited.
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How to use double or single brackets, parentheses, curly braces
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In Bash, test and [ are shell builtins.
The double bracket, which is a shell keyword, enables additional functionality. For example, you can use && and || instead of -a and -o and there's a regular expression matching operator =~....
Plot a legend outside of the plotting area in base graphics?
.... Normally this would get clipped to the plot region, but do par(xpd=TRUE) and with a bit of adjustment you can get a legend as far right as it can go:
set.seed(1) # just to get the same random numbers
par(xpd=FALSE) # this is usually the default
plot(1:3, rnorm(3), pch = 1, lty = 1, type = "o"...