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Count the number occurrences of a character in a string
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If you want the counts for a lot of the letters in a given string, Counter provides them all in a more succinct form. If you want the count for one letter from a lot of different strings, Counter provides no benefit.
– Brenden...
Measuring elapsed time with the Time module
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return ret
return with_profiling
def print_prof_data():
for fname, data in PROF_DATA.items():
max_time = max(data[1])
avg_time = sum(data[1]) / len(data[1])
print "Function %s called %d times. " % (fname, data[0]),
print 'Execution time max: %.3f, a...
Simple insecure two-way data “obfuscation”?
I'm looking for very simple obfuscation (like encrypt and decrypt but not necessarily secure) functionality for some data. It's not mission critical. I need something to keep honest people honest, but something a little stronger than ROT13 or Base64 .
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How to check that an element is in a std::set?
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The typical way to check for existence in many STL containers such as std::map, std::set, ... is:
const bool is_in = container.find(element) != container.end();
share
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In jQuery, how do I get the value of a radio button when they all have the same name?
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In your code, jQuery just looks for the first instance of an input with name q12_3, which in this case has a value of 1. You want an input with name q12_3 that is :checked.
$("#submit").click(() => {
const val = $('input[name=q12_3]:checked').val...
How to limit the maximum value of a numeric field in a Django model?
Django has various numeric fields available for use in models, e.g. DecimalField and PositiveIntegerField . Although the former can be restricted to the number of decimal places stored and the overall number of characters stored, is there any way to restrict it to storing only numbers within a ...
What is the difference between g++ and gcc?
...t is the difference between g++ and gcc? Which one of them should be used for general c++ development?
10 Answers
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Converting between datetime, Timestamp and datetime64
...t;>> numpy.__version__
'1.8.0.dev-7b75899'
It returns long because for numpy.datetime64 type .astype(datetime) is equivalent to .astype(object) that returns Python integer (long) on numpy-1.8.
To get datetime object you could:
>>> dt64.dtype
dtype('<M8[ns]')
>>> ns = ...
Useful code which uses reduce()? [closed]
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The other uses I've found for it besides + and * were with and and or, but now we have any and all to replace those cases.
foldl and foldr do come up in Scheme a lot...
Here's some cute usages:
Flatten a list
Goal: turn [[1, 2, 3], [4, 5], [6, 7...
What is the difference between '/' and '//' when used for division?
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In Python 3.x, 5 / 2 will return 2.5 and 5 // 2 will return 2. The former is floating point division, and the latter is floor division, sometimes also called integer division.
In Python 2.2 or later in the 2.x line, there is no difference for integers unless you perform a from __future__ im...