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SVG drop shadow using css3

...ow. Relevant bits from the example: <filter id="dropshadow" height="130%"> <feGaussianBlur in="SourceAlpha" stdDeviation="3"/> <!-- stdDeviation is how much to blur --> <feOffset dx="2" dy="2" result="offsetblur"/> <!-- how much to offset --> <feComponentTran...
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Performant Entity Serialization: BSON vs MessagePack (vs JSON)

...:2} is stored in a file and you want to update the value of "a" from 1 to 2000. With MessagePack, 1 uses only 1 byte but 2000 uses 3 bytes. So "b" must be moved backward by 2 bytes, while "b" is not modified. With BSON, both 1 and 2000 use 5 bytes. Because of this verbosity, you don't have to move...
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How to initialize all members of an array to the same value in Swift?

... 170 Actually, it's quite simple with Swift. As mentioned in the Apple's doc, you can initialize an a...
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Generate list of all possible permutations of a string

... 70 There are several ways to do this. Common methods use recursion, memoization, or dynamic program...
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Convert a character digit to the corresponding integer in C

... As per other replies, this is fine: char c = '5'; int x = c - '0'; Also, for error checking, you may wish to check isdigit(c) is true first. Note that you cannot completely portably do the same for letters, for example: char c = 'b'; int x = c - 'a'; // x is now not necessarily 1 Th...
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Checking for the correct number of arguments

... #!/bin/sh if [ "$#" -ne 1 ] || ! [ -d "$1" ]; then echo "Usage: $0 DIRECTORY" >&2 exit 1 fi Translation: If number of arguments is not (numerically) equal to 1 or the first argument is not a directory, output usage to stderr and exit with a failure status code. More friendly er...
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Is calculating an MD5 hash less CPU intensive than SHA family functions?

... Yes, MD5 is somewhat less CPU-intensive. On my Intel x86 (Core2 Quad Q6600, 2.4 GHz, using one core), I get this in 32-bit mode: MD5 411 SHA-1 218 SHA-256 118 SHA-512 46 and this in 64-bit mode: MD5 407 SHA-1 312 SHA-256 148 SHA-512 189 Figures are in megabytes ...
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Python 3: UnboundLocalError: local variable referenced before assignment [duplicate]

... rather than relying on Globals def function(Var1, Var2): if Var2 == 0 and Var1 > 0: print("Result One") elif Var2 == 1 and Var1 > 0: print("Result Two") elif Var1 < 1: print("Result Three") return Var1 - 1 function(1, 1) ...
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How can I convert an RGB image into grayscale in Python?

... 320 How about doing it with Pillow: from PIL import Image img = Image.open('image.png').convert('LA...
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List comprehension vs map

... map when using exactly the same function: $ python -mtimeit -s'xs=range(10)' 'map(hex, xs)' 100000 loops, best of 3: 4.86 usec per loop $ python -mtimeit -s'xs=range(10)' '[hex(x) for x in xs]' 100000 loops, best of 3: 5.58 usec per loop An example of how performance comparison gets completely r...