大约有 43,100 项符合查询结果（耗时：0.0408秒） [XML]
Pandas count(distinct) equivalent
...()
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...
The static keyword and its various uses in C++
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150
Variables:
static variables exist for the "lifetime" of the translation unit that it's defined...
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...
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 ...
Bootstrap carousel multiple frames at once
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14 Answers
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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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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
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143
Yes, it's subassignment in R using <- (or = or ->) that makes a copy of the whole object...
Insert spaces between words on a camel-cased token [duplicate]
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178
See: .NET - How can you split a "caps" delimited string into an array?
Especially:
Regex.Rep...
How to append contents of multiple files into one file
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10 Answers
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