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Pandas get topmost n records within each group
... 2
3 7 3 1
4 8 4 1
(Keep in mind that you might need to order/sort before, depending on your data)
EDIT: As mentioned by the questioner, use df.groupby('id').head(2).reset_index(drop=True) to remove the multindex and flatten the results.
>>> df.groupby('id').head(2).res...
Why do people hate SQL cursors so much? [closed]
...ause on a relational database, the performance of code using cursors is an order of magnitude worse than set-based operations.
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Renaming a branch in GitHub
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Maybe the order of two commands should be reversed (i.e. upload new name first, remove old after that)
– Vi.
Jan 2 '15 at 23:12
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Bytes of a string in Java
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@KorayTugay Yes, more or less. You could argue about the order of cause and effect, though. I'd be more inclined to state that a char is always 2 bytes because it is a primitive data type defined to be 2 bytes wide. (And that the UTF-16 representation was mainly a consequence of ...
How do I run Redis on Windows?
...dis 2.6 binaries.
So you'll need to download binaries from 2 branches in order to get all the necessary bits. Without further ado, here are the steps:
Download and extract the Redis binaries from the 2.6 branch
Copy all extracted binaries to c:\redis\bin
Create another folder at c:\redis\inst1
D...
What is the best way to get all the divisors of a number?
...s about killing performance. Problem two: the divisors are not returned in order.
– Tomasz Gandor
Dec 10 '14 at 14:37
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Why can't my program compile under Windows 7 in French? [closed]
... hommes.(cette)manger;
}
}
For further reference: Wikipedia Word Order
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edited Apr 2 '14 at 15:09
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About “*.d.ts” in TypeScript
...e libraries for typescript projects, an alternate solution was needed.
In order to do this, you can provide type declaration file in javascript library named as *.d.ts, like in above case mylib.d.ts. Declaration file only provides type declarations of functions and variables defined in respective j...
Why should I use document based database instead of relational database?
...e metadata fields which exists sometime (customer number, supplier number, order number, keep on file until, OCRed fulltext, etc). Usually you do not know in advance which metadata fields you will add within the next two years.
Things like CouchDB work much nicer for that kind of data than relationa...
Parse JSON String into a Particular Object Prototype in JavaScript
...stest. I guess issue with FF is that first test is slower than last, just order of execution matters. In chrome everything runs with almost same speed. I mean property access and nvocation of methods. Creatin is faster with new, but that's not so important. see: jsperf.com/prototype-change-test-88...