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How can I “unuse” a namespace?
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answered Oct 3 '08 at 17:39
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How can I check whether an array is null / empty?
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13 Answers
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What is the difference between substr and substring?
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3
@Pawel also when you want it to the end of the string (no second argument)
– André Chalella
Oct 20 '...
Is there any pythonic way to combine two dicts (adding values for keys that appear in both)?
...rom collections import Counter
>>> A = Counter({'a':1, 'b':2, 'c':3})
>>> B = Counter({'b':3, 'c':4, 'd':5})
>>> A + B
Counter({'c': 7, 'b': 5, 'd': 5, 'a': 1})
Counters are basically a subclass of dict, so you can still do everything else with them you'd normally do wit...
Ruby: What is the easiest way to remove the first element from an array?
...ther answer.
– Jay
Oct 15 '15 at 21:37
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Most efficient way to prepend a value to an array
...-O but certainly using the unshift method is more concise:
var a = [1, 2, 3, 4];
a.unshift(0);
a; // => [0, 1, 2, 3, 4]
[Edit]
This jsPerf benchmark shows that unshift is decently faster in at least a couple of browsers, regardless of possibly different big-O performance if you are ok with mo...
Pandas selecting by label sometimes return Series, sometimes returns DataFrame
... other ways, but in my opinion this is the cleanest.
In [2]: type(df.loc[[3]])
Out[2]: pandas.core.frame.DataFrame
In [3]: type(df.loc[[1]])
Out[3]: pandas.core.frame.DataFrame
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What is the difference between int, Int16, Int32 and Int64?
What is the difference between int , System.Int16 , System.Int32 and System.Int64 other than their sizes?
10 Answers
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kill -3 to get java thread dump
I am using kill -3 command to see the JVM's thread dump in unix. But where can I find the output of this kill command? I am lost!!
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