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C# DateTime to “YYYYMMDDHHMMSS” format
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List All Redis Databases
...atabases is fixed, and set in the configuration file. By default, you have 16 databases. Each database is identified by a number (not a name).
You can use the following command to know the number of databases:
CONFIG GET databases
1) "databases"
2) "16"
You can use the following command to list ...
Common MySQL fields and their appropriate data types
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71
Someone's going to post a much better answer than this, but just wanted to make the point that p...
Does the ternary operator exist in R?
... returns the latest evaluation, if-else is equivalent to ?:.
> a <- 1
> x <- if(a==1) 1 else 2
> x
[1] 1
> x <- if(a==2) 1 else 2
> x
[1] 2
The power of R is vectorization. The vectorization of the ternary operator is ifelse:
> a <- c(1, 2, 1)
> x <- ifelse(a=...
Convert tuple to list and back
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answered May 6 '14 at 14:27
KhonixKhonix
3,32311 gold badge1111 silver badges1515 bronze badges
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Pandas dataframe get first row of each group
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>>> df.groupby('id').first()
value
id
1 first
2 first
3 first
4 second
5 first
6 first
7 fourth
If you need id as column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 seco...
Selecting pandas column by location
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155
Two approaches that come to mind:
>>> df
A B C D
0...
How does zip(*[iter(s)]*n) work in Python?
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111
iter() is an iterator over a sequence. [x] * n produces a list containing n quantity of x, i.e...
how to override left:0 using CSS or Jquery?
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answered Apr 11 '12 at 9:06
Jan HančičJan Hančič
48.2k1515 gold badges8787 silver badges9494 bronze badges
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