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Get the week start date and week end date from week number
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3
Bear in mind that setting DATEFIRST to anything other than 7 breaks this.
– Tomalak
Aug 12 '09 at 16:...
Creating a new column based on if-elif-else condition
...df['C'] = df.apply(f, axis=1)
In [2]: df
Out[2]:
A B C
a 2 2 0
b 3 1 1
c 1 3 -1
Of course, this is not vectorized so performance may not be as good when scaled to a large number of records. Still, I think it is much more readable. Especially coming from a SAS background.
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Count number of matches of a regex in Javascript
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/*
* Example
*/
const count = (str) => {
const re = /[a-z]{3}/g
return ((str || '').match(re) || []).length
}
const str1 = 'abc, def, ghi'
const str2 = 'ABC, DEF, GHI'
console.log(`'${str1}' has ${count(str1)} occurrences of pattern '/[a-z]{3}/g'`)
console.log(`'${str2}' ...
In-memory size of a Python structure
Is there a reference for the memory size of Python data stucture on 32- and 64-bit platforms?
7 Answers
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What are “named tuples” in Python?
Reading the changes in Python 3.1 , I found something... unexpected:
11 Answers
11
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Convert Elixir string to integer or float
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edited Jul 10 '18 at 13:06
Ronan Boiteau
7,52566 gold badges2828 silver badges4343 bronze badges
ans...
WPF ToolBar: how to remove grip and overflow
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153
The grip can be removed by setting the attached property ToolBarTray.IsLocked="True" on the Tool...
pytest: assert almost equal
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I noticed that this question specifically asked about py.test. py.test 3.0 includes an approx() function (well, really class) that is very useful for this purpose.
import pytest
assert 2.2 == pytest.approx(2.3)
# fails, default is ± 2.3e-06
assert 2.2 == pytest.approx(2.3, 0.1)
# passes
# al...
vertical & horizontal lines in matplotlib
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3 Answers
3
Active
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filter items in a python dictionary where keys contain a specific string
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183
How about a dict comprehension:
filtered_dict = {k:v for k,v in d.iteritems() if filter_string ...