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Is short-circuiting logical operators mandated? And evaluation order?
Does the ANSI standard mandate the logical operators to be short-circuited, in either C or C++?
7 Answers
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Find row where values for column is maximal in a pandas DataFrame
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Use the pandas idxmax function. It's straightforward:
>>> import pandas
>>> import numpy as np
>>> df = pandas.DataFrame(np.random.randn(5,3),columns=['A','B','C'])
>>> df
A B ...
How can I add new keys to a dictionary?
...y by assigning a value
to that key. If the key doesn't exist, it's added and points to that
value. If it exists, the current value it points to is overwritten.
—R. Navega
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Does Python have an ordered set?
...s referred to from the Python 2 Documentation. This runs on Py2.6 or later and 3.0 or later without any modifications. The interface is almost exactly the same as a normal set, except that initialisation should be done with a list.
OrderedSet([1, 2, 3])
This is a MutableSet, so the signature for ...
Position icons into circle
...can I position several <img> elements into a circle around another and have those elements all be clickable links as well? I want it to look like the picture below, but I have no idea how to achieve that effect.
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How to use PHP OPCache?
PHP 5.5 has been released and it features a new code caching module called OPCache, but there doesn't appear to be any documentation for it.
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How to compare dates in datetime fields in Postgresql?
...3 12:20:00). This column has the value as timestamp for all rows currently and have the same date part(2013-05-03) but difference in time part.
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Find if current time falls in a time range
...ount the number of matches? For example I want to count how many saturdays and sundays are in the range.
– pbies
Sep 4 '13 at 19:28
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Efficient way to insert a number into a sorted array of numbers?
I have a sorted JavaScript array, and want to insert one more item into the array such the resulting array remains sorted. I could certainly implement a simple quicksort-style insertion function:
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Reduce, fold or scan (Left/Right)?
... operator's two arguments). This way we can cumulate a result.
reduceLeft and reduceRight cumulate a single result.
foldLeft and foldRight cumulate a single result using a start value.
scanLeft and scanRight cumulate a collection of intermediate cumulative results using a start value.
Accumulate...