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Pandas groupby: How to get a union of strings
...d aggregations where we can groupby, aggregate and at the same time assign new names to our columns. This way we won't get the MultiIndex columns, and the column names make more sense given the data they contain:
aggregate and get a list of strings
grp = df.groupby('A').agg(B_sum=('B','sum'),
...
How do you crash a JVM?
...args) {
Object[] o = null;
while (true) {
o = new Object[] {o};
}
}
}
This leads to a stack overflow in the GC so you will get no StackOverflowError but a real crash including a hs_err* file.
...
CSS Progress Circle [closed]
...first solutions progress? could it be done with a data element? I'm rather new to animation
– anthonytherockjohnson
Mar 30 '17 at 8:37
...
How exactly does work?
... Mar 9 '11 at 19:09
Mark At Ramp51Mark At Ramp51
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...
Break or return from Java 8 stream forEach?
...l code here
if(some_exceptional_condition_met) {
throw new BreakException();
}
}
}
catch (BreakException e) {
// here you know that your condition has been met at least once
}
Notice that the try...catch is not around the lambda expression, but rather around the ...
Is pass-by-value a reasonable default in C++11?
...
@AaronMcDaid This is old news, in the sense that's something you always had to be aware of even before C++11. And nothing much has changed with respect to that.
– Luc Danton
Oct 22 '13 at 15:51
...
SQLite - UPSERT *not* INSERT or REPLACE
...table: ID, NAME, ROLE
BAD: This will insert or replace all columns with new values for ID=1:
INSERT OR REPLACE INTO Employee (id, name, role)
VALUES (1, 'John Foo', 'CEO');
BAD: This will insert or replace 2 of the columns... the NAME column will be set to NULL or the default value:
INSE...
Mean per group in a data.frame [duplicate]
...
summarise _each is deprecated in new version. What should I use intead? I tried summarise_at or _if or_all. but didn't work .
– ferrelwill
Dec 4 '17 at 22:22
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How do I catch a numpy warning like it's an exception (not just for testing)?
... barycentric style one to avoid using an explicit for-loop as opposed to a Newton's divided difference style one. The problem I have is that I need to catch a division by zero, but Python (or maybe numpy) just makes it a warning instead of a normal exception.
...
jQuery/JavaScript to replace broken images
...dth == 0 ) {
// image was broken, replace with your new image
this.src = 'http://www.tranism.com/weblog/images/broken_ipod.gif';
}
});
});
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