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PHP Foreach Pass by Reference: Last Element Duplicating? (Bug?)
... $item is still a reference to some value which is also being used by $arr[2]. So each foreach call in the second loop, which does not call by reference, replaces that value, and thus $arr[2], with the new value.
So loop 1, the value and $arr[2] become $arr[0], which is 'foo'.
Loop 2, the value and ...
How to extract the decision rules from scikit-learn decision-tree?
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21 Answers
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How to pad zeroes to a string?
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2506
Strings:
>>> n = '4'
>>> print(n.zfill(3))
004
And for numbers:
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How can I verify if one list is a subset of another?
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Boris
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answered May 16 '13 at 4:59
Yann VernierYann Vern...
Circle-Rectangle collision detection (intersection)
How can I tell whether a circle and a rectangle intersect in 2D Euclidean space? (i.e. classic 2D geometry)
25 Answers
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How do I capture the output into a variable from an external process in PowerShell?
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JNKJNK
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How do I merge a list of dicts into a single dict?
... d in L:
... result.update(d)
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>>> result
{'a':1,'c':1,'b':2,'d':2}
As a comprehension:
# Python >= 2.7
{k: v for d in L for k, v in d.items()}
# Python < 2.7
dict(pair for d in L for pair in d.items())
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Multiple glibc libraries on a single host
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It is very possible to have multiple versions of glibc on the same system (we do that every da...
Truncate number to two decimal places without rounding
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How do I delete rows in a data frame?
...he '-' operator.
So, assuming the data.frame is called myData:
myData[-c(2, 4, 6), ] # notice the -
Of course, don't forget to "reassign" myData if you wanted to drop those rows entirely---otherwise, R just prints the results.
myData <- myData[-c(2, 4, 6), ]
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