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Scala best way of turning a Collection into a Map-by-key?

...Traversable[V].mapBy( V => K) were better! – oxbow_lakes Jul 14 '10 at 21:17 7 Be aware that t...
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HTML5 Email Validation

... matches the following regular expression: /^[a-zA-Z0-9.!#$%&’*+/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$/ Use the required attribute and a pattern attribute to require the value to match the regex pattern. <input type="text" pattern="/^[a-zA-Z0-9.!#$%&’*+/=?^_`{|}~...
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What is a plain English explanation of “Big O” notation?

... -1: This is blatantly wrong: _"BigOh is relative representation of complexity of algorithm". No. BigOh is an asymptotic upper bound and exists quite well independent of computer science. O(n) is linear. No, you are confusing BigOh with theta. log n is O(...
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How do I install an R package from source?

...hen use install.packages() and set the repos=NULL: install.packages(path_to_file, repos = NULL, type="source") Where path_to_file would represent the full path and file name: On Windows it will look something like this: "C:\\RJSONIO_0.2-3.tar.gz". On UNIX it will look like this: "/home/blah/R...
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How to get RGB values from UIColor?

...rView.backgroundColor;//line 2 CGColorRef colorRef = [color CGColor]; int _countComponents = CGColorGetNumberOfComponents(colorRef); if (_countComponents == 4) { const CGFloat *_components = CGColorGetComponents(colorRef); CGFloat red = _components[0]; CGFloat green = _components[1...
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jQuery Ajax POST example with PHP

...an access the values posted by jQuery.ajax // through the global variable $_POST, like this: $bar = isset($_POST['bar']) ? $_POST['bar'] : null; Note: Always sanitize posted data, to prevent injections and other malicious code. You could also use the shorthand .post in place of .ajax in the above...
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Min/Max-value validators in asp.net mvc

...MaxValueAttribute : ValidationAttribute { private readonly int _maxValue; public MaxValueAttribute(int maxValue) { _maxValue = maxValue; } public override bool IsValid(object value) { return (int) value <= _maxValue; ...
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How to determine whether a given Linux is 32 bit or 64 bit?

... Try uname -m. Which is short of uname --machine and it outputs: x86_64 ==> 64-bit kernel i686 ==> 32-bit kernel Otherwise, not for the Linux kernel, but for the CPU, you type: cat /proc/cpuinfo or: grep flags /proc/cpuinfo Under "flags" parameter, you will see various value...
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How do I get indices of N maximum values in a NumPy array?

...t;> a = [1, 3, 2, 4, 5] >>> heapq.nlargest(3, range(len(a)), a.__getitem__) [4, 3, 1] If you use Python 2, use xrange instead of range. Source: heapq — Heap queue algorithm share | ...
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ASP.NET MVC: No parameterless constructor defined for this object

...ot know if it makes sense... something like that. – H_He Jul 28 '14 at 11:52 1 Tuples... maybe fo...