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Is SQL or even TSQL Turing Complete?
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Qantas 94 Heavy
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answered Sep 28 '11 at 7:59
Jan de VosJan de Vos
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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 ...
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 ...
Does Python support short-circuiting?
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answered Apr 5 '10 at 18:20
Alex MartelliAlex Martelli
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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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Why use strong named assemblies?
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edited Jun 10 at 14:18
Jan Nils Ferner
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Android Gradle plugin 0.7.0: “duplicate files during packaging of APK”
Using Android Gradle plugin 0.7.0 with the following build.gradle :
20 Answers
20
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How do I get SUM function in MySQL to return '0' if no values are found?
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307
Use COALESCE to avoid that outcome.
SELECT COALESCE(SUM(column),0)
FROM table
WHERE ...
T...
Return index of greatest value in an array
... works on old browsers:
function indexOfMax(arr) {
if (arr.length === 0) {
return -1;
}
var max = arr[0];
var maxIndex = 0;
for (var i = 1; i < arr.length; i++) {
if (arr[i] > max) {
maxIndex = i;
max = arr[i];
}
}
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Why is GHC so large/big?
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edited Feb 1 '11 at 20:04
answered Feb 1 '11 at 19:48
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