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Extract a regular expression match
...rary(stringr)
str_locate("aaa12xxx", "[0-9]+")
# start end
# [1,] 4 5
str_extract("aaa12xxx", "[0-9]+")
# [1] "12"
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What is tail recursion?
...function that adds the first N natural numbers. (e.g. sum(5) = 1 + 2 + 3 + 4 + 5 = 15).
Here is a simple JavaScript implementation that uses recursion:
function recsum(x) {
if (x === 1) {
return x;
} else {
return x + recsum(x - 1);
}
}
If you called recsum(5), this i...
How to use z-index in svg elements?
...ion is the next major release and still supports the above features.
3.4. Rendering order
Elements in SVG are positioned in three dimensions. In addition to their position on the x and y axis of the SVG viewport, SVG elements are also positioned on the z axis. The position on the z-axis def...
Code Golf: Collatz Conjecture
...>> 123 --> 370 --> 185 --> 556 --> 278 --> 139 --> 418 --> 209 --> 628 --> 314
; >> --> 157 --> 472 --> 236 --> 118 --> 59 --> 178 --> 89 --> 268 --> 134 --> 67
; >> --> 202 --> 101 --> 304 --> 152 --> 76 -->...
jQuery: Count number of list elements?
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gsamaras
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answered Mar 3 '09 at 11:12
cletuscletus...
Redis connection to 127.0.0.1:6379 failed - connect ECONNREFUSED
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piggybackpiggyback
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Pass a PHP array to a JavaScript function [duplicate]
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4 Answers
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How do I check if an integer is even or odd? [closed]
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449
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Use the modulo (%) operator to check if there's a remainder when dividing b...
“Unresolved inclusion” error with Eclipse CDT for C standard library headers
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14 Answers
14
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How to pass variable number of arguments to a PHP function
...he output :
int 3
array
0 => int 10
1 => string 'glop' (length=4)
2 => string 'test' (length=4)
ie, 3 parameters ; exactly like iof the function was called this way :
test(10, 'glop', 'test');
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