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PHP - Modify current object in foreach loop
...horter (see comment by Paystey)
Per the PHP foreach documentation:
In order to be able to directly modify array elements within the loop precede $value with &. In that case the value will be assigned by reference.
...
Abstract Class vs Interface in C++ [duplicate]
...an abstract class that initializes OpenGL, sets up the window environment, etc. and then you can derive from this class and implement custom code for e.g. the rendering process and handling user input:
// Abstract class for an OpenGL app.
// Creates rendering window, initializes OpenGL;
// client ...
What is pip's equivalent of `npm install package --save-dev`?
...e to use) it can handle many files and environments(test, dev, production, etc. ). It also has command to upgrade all/any of your dependencies.
installation
pipm install pkg-name
installation as development dependency
pipm install pkg-name --dev
installation as testing dependency
pipm install...
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...
Attach to a processes output for viewing
...t I did:
watch cat /dev/vcsa1
Obviously you'd want to use vcsa2, vcsa3, etc., depending on which terminal was being used.
So long as my terminal window was of the same width as the terminal that the command was being run on, I could see a snapshot of their current output every two seconds. The o...
How Big can a Python List Get?
... 12000 elements. Will I still be able to run list methods such as sorting, etc?
10 Answers
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Rebuild IntelliJ project indexes
IntelliJ IDEA 10.5.1 is reporting zero usages for all method, classes etc.
2 Answers
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Can you have multiline HTML5 placeholder text in a ?
...g. The downside of this is that other browsers than chrome, safari, webkit-etc. don't even show the first line:
<textarea id="text2" placeholder="." rows="10"></textarea>
then add the rest of the line by css:
#text2::-webkit-input-placeholder{
color:transparent;
}
#text2::-we...
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 ...