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How to group dataframe rows into list in pandas groupby?
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You can do this using groupby to group on the column of interest and then apply list to every group:
In [1]: df = pd.DataFrame( {'a':['A','A','B','B','B','C'], 'b':[1,2,5,5,4,6]})
df
Out[1]:
a b
0 A 1
1 A 2
2 B 5
3 B...
SQL: How to properly check if a record exists
While reading some SQL Tuning-related documentation, I found this:
9 Answers
9
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How can I convert a zero-terminated byte array to string?
.... You should save that number and then use it to create your string. If n is the number of bytes read, your code would look like this:
s := string(byteArray[:n])
To convert the full string, this can be used:
s := string(byteArray[:len(byteArray)])
This is equivalent to:
s := string(byteArray)
If...
What difference is there between WebClient and HTTPWebRequest classes in .NET?
What difference is there between the WebClient and the HttpWebRequest classes in .NET? They both do very similar things. In fact, why weren't they merged into one class (too many methods/variables etc may be one reason but there are other classes in .NET which breaks that rule).
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How to find memory leak in a C++ code/project?
I am a C++ programmer on the Windows platform. I am using Visual Studio 2008.
19 Answers
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Maximum number of threads in a .NET app?
What is the maximum number of threads you can create in a C# application? And what happens when you reach this limit? Is an exception of some kind thrown?
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HTTP status code for a partial successful request
...n application that sends messages to users. In a post request a XML string is transferred that consists of all the users that should receive that particular message. If any of the users in the list do not exist I give the list of missing users back to the client for further evaluation.
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How do I mock an open used in a with statement (using the Mock framework in Python)?
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The way to do this has changed in mock 0.7.0 which finally supports mocking the python protocol methods (magic methods), particularly using the MagicMock:
http://www.voidspace.org.uk/python/mock/magicmock.html
An example of mocking open as...
Do something if screen width is less than 960 px
How can I make jQuery do something if my screen width is less than 960 pixels? The code below always fires the 2nd alert, regardless of my window size:
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EF Code First foreign key without navigation property
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With EF Code First Fluent API it is impossible. You always need at least one navigation property to create a foreign key constraint in the database.
If you are using Code First Migrations you have the option to add a new code based migration on the package ...