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How can I implode an array while skipping empty array items?
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212
You can use array_filter():
If no callback is supplied, all entries of input equal to FALSE...
Aren't Python strings immutable? Then why does a + “ ” + b work?
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185
First a pointed to the string "Dog". Then you changed the variable a to point at a new string...
How to select a single field for all documents in a MongoDB collection?
In my MongoDB, I have a student collection with 10 records having fields name and roll . One record of this collection is:
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Pandas count(distinct) equivalent
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Example:
In [2]: table
Out[2]:
CLIENTCODE YEARMONTH
0 1 201301
1 1 201301
2 2 201301
3 1 201302
4 2 201302
5 2 201302
6 3 201302
In [3]: table.groupby('YEARMONTH').CLIENTCODE.nunique()
Out[3...
Explicitly select items from a list or tuple
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154
list( myBigList[i] for i in [87, 342, 217, 998, 500] )
I compared the answers with python ...
Rotating and spacing axis labels in ggplot2
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1159
Change the last line to
q + theme(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust...
Bootstrap carousel multiple frames at once
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14 Answers
14
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Cost of len() function
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It's O(1) (constant time, not depending of actual length of the element - very fast) on every type you've mentioned, plus set and others such as array.array.
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How to append contents of multiple files into one file
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10 Answers
10
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