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How to find the length of a string in R
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424
See ?nchar. For example:
> nchar("foo")
[1] 3
> set.seed(10)
> strn <- paste(sampl...
Converting a column within pandas dataframe from int to string
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142
In [16]: df = DataFrame(np.arange(10).reshape(5,2),columns=list('AB'))
In [17]: df
Out[17]:
...
How to print to console in pytest?
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226
By default, py.test captures the result of standard out so that it can control how it prints i...
Why does parseInt yield NaN with Array#map?
... element.
In this case, you ended up calling parseInt with radix 0, 1 and 2 in turn. The first is the same as not supplying the parameter, so it defaulted based on the input (base 10, in this case). Base 1 is an impossible number base, and 3 is not a valid number in base 2:
parseInt('1', 0); // ...
Creating dataframe from a dictionary where entries have different lengths
...hon 3.x:
import pandas as pd
import numpy as np
d = dict( A = np.array([1,2]), B = np.array([1,2,3,4]) )
pd.DataFrame(dict([ (k,pd.Series(v)) for k,v in d.items() ]))
Out[7]:
A B
0 1 1
1 2 2
2 NaN 3
3 NaN 4
In Python 2.x:
replace d.items() with d.iteritems().
...
How to find the operating system version using JavaScript?
...onsole.log(navigator);
You'll see something like this
# platform = Win32
# appCodeName = Mozilla
# appName = Netscape
# appVersion = 5.0 (Windows; en-US)
# language = en-US
# mimeTypes = [object MimeTypeArray]
# oscpu = Windows NT 5.1
# vendor = Firefox
# vendorSub = 1.0.7
# product = Gecko
# pr...
Python integer division yields float
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292
Take a look at PEP-238: Changing the Division Operator
The // operator will be available t...
Get last result in interactive Python shell
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243
Underscore.
>>> 5+5
10
>>> _
10
>>> _ + 5
15
>>> _
15
...
Converting NumPy array into Python List structure?
How do I convert a NumPy array to a Python List (for example [[1,2,3],[4,5,6]] ), and do it reasonably fast?
5 Answers
...
What is the ideal data type to use when storing latitude / longitude in a MySQL database?
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21 Answers
21
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