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Apply pandas function to column to create multiple new columns?
... updating the row directly like this ended up being surprisingly slow - an order of magnitude slower than the apply with 'expand' + pd.concat solutions
– Dmytro Bugayev
Jun 30 at 17:33
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What did MongoDB not being ACID compliant before v4 really mean?
...ent.
If you need to remove an item from inventory and add it to someone's order at the same time - you can't. Unless those two things - inventory and orders - exist in the same document (which they probably do not).
I encountered this very same issue in an application I am working on and had two ...
Can I access variables from another file?
...};
secondfile.js:
do_something_with(colors.background);
Note that the order in which you load the script files is significant for some browsers (IE6 for sure, maybe others)
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Can I force a page break in HTML printing?
...
Add a CSS class called "pagebreak" (or "pb"), like so:
@media print {
.pagebreak { page-break-before: always; } /* page-break-after works, as well */
}
Then add an empty DIV tag (or any block element that generates a box) where you wan...
What is the most “pythonic” way to iterate over a list in chunks?
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Finally got a chance to play around with this in a python session. For those who are as confused as I was, this is feeding the same iterator to izip_longest multiple times, causing it to consume successive values of the same seq...
How to construct a set out of list items in python?
...on 3,
my_list = [*my_set]
to create a list from a set.
Just note that the order of the elements in a list is generally lost when converting the list to a set since a set is inherently unordered. (One exception in CPython, though, seems to be if the list consists only of non-negative integers, but I...
How to toggle a value in Python
...>> x
1
The technique generalizes to any pair of integers. The xor-by-one step is replaced with a xor-by-precomputed-constant:
>>> A = 205
>>> B = -117
>>> t = A ^ B # precomputed toggle constant
>>> x = A
>>> x ^= t # toggle
>...
Apply multiple functions to multiple groupby columns
...ion.
I recommend making a single custom function that returns a Series of all the aggregations. Use the Series index as labels for the new columns:
def f(x):
d = {}
d['a_sum'] = x['a'].sum()
d['a_max'] = x['a'].max()
d['b_mean'] = x['b'].mean()
d['c_d_prodsum'] = (x['c'] * x['d...
Have a reloadData for a UITableView animate when changing
...the modes I have a different number of sections and cells per section. Ideally, it would do some cool animation when the table grows or shrinks.
...
What is the difference between compile and link function in angularjs
...on this for a couple of days, and I feel that a bit more explanation is in order.
Basically, the docs mention that the separation is largely a performance enhancement. I would reiterate that the compile phase is mainly used when you need to modify the DOM BEFORE the sub-elements themselves are comp...