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Pandas dataframe get first row of each group
...column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6 first
6 7 fourth
To get n first records, you can use head():
>>> df.groupby('id').head(2).reset_index(drop=True)
id value
0 ...
C# 5 async CTP: why is internal “state” set to 0 in generated code before EndAwait call?
...t. Many thanks to him - and please visit his blog, which rocks.
The value 0 here is only special because it's not a valid state which you might be in just before the await in a normal case. In particular, it's not a state which the state machine may end up testing for elsewhere. I believe that usin...
Insert a row to pandas dataframe
...df.sort_index() # sorting by index
And you get, as desired:
A B C
0 2 3 4
1 5 6 7
2 7 8 9
See in Pandas documentation Indexing: Setting with enlargement.
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Does Python support short-circuiting?
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answered Apr 5 '10 at 18:20
Alex MartelliAlex Martelli
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What are Vertex Array Objects?
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102
"Vertex Array Object" is brought to you by the OpenGL ARB Subcommittee for Silly Names.
Think ...
Warning: Found conflicts between different versions of the same dependent assembly
I am currently developing a .NET application, which consists of 20 projects. Some of those projects are compiled using .NET 3.5, some others are still .NET 2.0 projects (so far no problem).
...
How to remove leading zeros from alphanumeric text?
...s leading zeroes, but leaves one if necessary (i.e. it wouldn't just turn "0" to a blank string).
s.replaceFirst("^0+(?!$)", "")
The ^ anchor will make sure that the 0+ being matched is at the beginning of the input. The (?!$) negative lookahead ensures that not the entire string will be matched....
Why use strong named assemblies?
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edited Jun 10 at 14:18
Jan Nils Ferner
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Javascript sort array by two fields
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104
grouperArray.sort(function (a, b) {
var aSize = a.gsize;
var bSize = b.gsize;
var a...
Android Gradle plugin 0.7.0: “duplicate files during packaging of APK”
Using Android Gradle plugin 0.7.0 with the following build.gradle :
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