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Does Python support short-circuiting?
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answered Apr 5 '10 at 18:20
Alex MartelliAlex Martelli
724k148148 gold badges11251125 silver badges13241324 bronze badges
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ValueError: math domain error
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edited Sep 3 '17 at 20:49
answered Apr 8 '13 at 23:06
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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...
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...
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 ...
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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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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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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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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What is the Ruby (spaceship) operator?
...ther language that supports it. Basically instead of returning 1 (true) or 0 (false) depending on whether the arguments are equal or unequal, the spaceship operator will return 1, 0, or −1 depending on the value of the left argument relative to the right argument.
a <=> b :=
if a < b t...