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count the frequency that a value occurs in a dataframe column
...38]:
df['a'].value_counts()
Out[38]:
b 3
a 2
s 2
dtype: int64
If you wanted to add frequency back to the original dataframe use transform to return an aligned index:
In [41]:
df['freq'] = df.groupby('a')['a'].transform('count')
df
Out[41]:
a freq
0 a 2
1 b 3
2 s 2
3 s...
How to set a selected option of a dropdown list control using angular JS
... a selected option of a dropdown list control using angular JS. Forgive me if this is ridiculous but I am new with Angular JS
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Using Git, show all commits that are in one branch, but not the other(s)
... to my current branch which have not been applied to any other branch [or, if this is not possible without some scripting, how does one see all commits in one branch which have not been applied to another given branch?].
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How to get a number of random elements from an array?
...ew Array(n),
len = arr.length,
taken = new Array(len);
if (n > len)
throw new RangeError("getRandom: more elements taken than available");
while (n--) {
var x = Math.floor(Math.random() * len);
result[n] = arr[x in taken ? taken[x] : x];
tak...
How do I set the size of Emacs' window?
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If you want to change the size according to resolution you can do something like this (adjusting the preferred width and resolutions according to your specific needs):
(defun set-frame-size-according-to-resolution ()
(inte...
Use of alloc init instead of new
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There are a bunch of reasons here: http://macresearch.org/difference-between-alloc-init-and-new
Some selected ones are:
new doesn't support custom initializers (like initWithString)
alloc-init is more explicit than new
General opinion seems to be that you should use whatever you...
How to switch to the new browser window, which opens after click on the button?
...Handle);
}
// Perform the actions on new window
// Close the new window, if that window no more required
driver.close();
// Switch back to original browser (first window)
driver.switchTo().window(winHandleBefore);
// Continue with original browser (first window)
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Numpy `logical_or` for more than two arguments
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If you're asking about numpy.logical_or, then no, as the docs explicitly say, the only parameters are x1, x2, and optionally out:
numpy.logical_or(x1, x2[, out]) = <ufunc 'logical_or'>
You can of course chain to...
Regular expression for a hexadecimal number?
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That could be shortified to /0x[\da-f]/i, but otherwise, +1.
– Niklas B.
Feb 10 '12 at 1:13
20
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Fixed size queue which automatically dequeues old values upon new enques
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@RichardSchneider If you need to handle concurrency issues yourself then it would be a good idea to swap the ConcurrentQueue<T> object for a Queue<T> object which is more lightweight.
– 0b101010
...