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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
... ...:
In [3]: df = DataFrame({'a': [1,2,3], 'b': [2,3,4]})
In [4]: df
Out[4]:
a b
0 1 2
1 2 3
2 3 4
In [5]: df["A1"], df["A2"] = zip(*df["a"].map(calculate))
In [6]: df
Out[6]:
a b A1 A2
0 1 2 2 3
1 2 3 4 6
2 3 4 6 9
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How do I update a GitHub forked repository?
...t fetch upstream
# Make sure that you're on your master branch:
git checkout master
# Rewrite your master branch so that any commits of yours that
# aren't already in upstream/master are replayed on top of that
# other branch:
git rebase upstream/master
If you don't want to rewrite the history...
What's wrong with cplusplus.com?
...d::remove works with a pair of iterators only and does not know anything about the container which actually contains the items. In fact, it's not possible for std::remove to know the underlying container, because there is no way it can go from a pair of iterators to discover about the container to w...
If vs. Switch Speed
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Good answer, interesting about the hash table.
– BobbyShaftoe
Jan 14 '09 at 23:19
4
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I need to pop up and trash away a “middle” commit in my master branch. How can I do it?
...t never existed. This will be a problem if you've pushed the master branch out to any other repos. If you try to push after a rebase in this case, git will give you a reject non fast-forward merges error.
Revert is the correct solution when the branch has been shared with other repos. git revert af...
git shallow clone (clone --depth) misses remote branches
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florianb: what is your git version? thanks for trying it out. I did the --depth 1 on 1.7.1 just now it shows all the remote branches. updated the question with this. +1 for verifying the problem.
– minghua
May 17 '14 at 19:12
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PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?
This is what I've read so far about PDO::ATTR_EMULATE_PREPARES :
7 Answers
7
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What does the restrict keyword mean in C++?
...g.
It clearly shows how as it allows to save one assembly instruction.
Without restrict:
void f(int *a, int *b, int *x) {
*a += *x;
*b += *x;
}
Pseudo assembly:
load R1 ← *x ; Load the value of x pointer
load R2 ← *a ; Load the value of a pointer
add R2 += R1 ; Perform Addition
set...
How to align checkboxes and their labels consistently cross-browsers
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I disagree with the suggestion about using conditional comments. Keep the *foobar CSS hack. That works well, is used by frameworks like YUI, and allows you to keep together what belongs together.
– ebruchez
Jan 30 '09 a...
Change color of PNG image via CSS?
...ld use:
<a class="fa fa-thumbs-up"></a>
EDIT 2:
Just found out github also uses its own icon font: Octicons
It's free to download. They also have some tips on how to create your very own icon fonts.
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