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cartesian product in pandas
...port DataFrame, merge
df1 = DataFrame({'key':[1,1], 'col1':[1,2],'col2':[3,4]})
df2 = DataFrame({'key':[1,1], 'col3':[5,6]})
merge(df1, df2,on='key')[['col1', 'col2', 'col3']]
Output:
col1 col2 col3
0 1 3 5
1 1 3 6
2 2 4 5
3 2 4 6
See here f...
How do I specify a password to 'psql' non-interactively?
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154
From the official documentation:
It is also convenient to have a ~/.pgpass file to avoid reg...
sql query to return differences between two tables
...easchftreaschf
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How to sum a variable by group
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404
Using aggregate:
aggregate(x$Frequency, by=list(Category=x$Category), FUN=sum)
Category x
...
Add one row to pandas DataFrame
...))
>>> df
lib qty1 qty2
0 name0 3 3
1 name1 2 4
2 name2 2 8
3 name3 2 1
4 name4 9 6
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combinations between two lists?
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edited Apr 5 at 20:47
Bill
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answered Oct 1...
Multi-line tooltips in Java?
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148
If you wrap the tooltip in <html> and </html> tags, you can break lines with <br...
Disable, but not uninstall Resharper 4.x onwards
Any ideas on how to disable, but not uninstall Resharper 4.x or above?
10 Answers
10
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Handle Guzzle exception and get HTTP body
I would like to handle errors from Guzzle when the server returns 4xx and 5xx status codes. I make a request like this:
5 A...
Ruby: How to turn a hash into HTTP parameters?
... AmanBob Aman
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