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What is the optimal Jewish toenail cutting algorithm?
...mport ifilter, permutations
validseqs = ifilter(isValid, permutations([1,2,3,4,5]))
for i in validseqs:
print i
(1, 3, 5, 2, 4)
(1, 4, 2, 5, 3)
(2, 4, 1, 3, 5)
(2, 4, 1, 5, 3)
(2, 5, 3, 1, 4)
(3, 1, 4, 2, 5)
(3, 1, 5, 2, 4)
(3, 5, 1, 4, 2)
(3, 5, 2, 4, 1)
(4, 1, 3, 5, 2)
(4, 2, 5, 1, 3)
(4, 2, ...
Logical operators for boolean indexing in Pandas
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3 Answers
3
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Why does [5,6,8,7][1,2] = 8 in JavaScript?
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3 Answers
3
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Replacing NAs with latest non-NA value
...ry(zoo)
az <- zoo(1:6)
bz <- zoo(c(2,NA,1,4,5,2))
na.locf(bz)
1 2 3 4 5 6
2 2 1 4 5 2
na.locf(bz, fromLast = TRUE)
1 2 3 4 5 6
2 1 1 4 5 2
cz <- zoo(c(NA,9,3,2,3,2))
na.locf(cz)
2 3 4 5 6
9 3 2 3 2
shar...
What does -1 mean in numpy reshape?
...numpy allow us to give one of new shape parameter as -1 (eg: (2,-1) or (-1,3) but not (-1, -1)). It simply means that it is an unknown dimension and we want numpy to figure it out. And numpy will figure this by looking at the 'length of the array and remaining dimensions' and making sure it satisfi...
Remove empty elements from an array in Javascript
... to remove null or undefined values:
var array = [0, 1, null, 2, "", 3, undefined, 3,,,,,, 4,, 4,, 5,, 6,,,,];
var filtered = array.filter(function (el) {
return el != null;
});
console.log(filtered);
It will depend on what you consider to be "empty" for example, if you were d...
Grouping functions (tapply, by, aggregate) and the *apply family
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1344
+100
R has ...
Validating IPv4 addresses with regexp
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36 Answers
36
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How to slice an array in Bash
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317
See the Parameter Expansion section in the Bash man page. A[@] returns the contents of the arr...