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What does “exited with code 9009” mean during this build?
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String concatenation vs. string substitution in Python
...meit.Timer('so_q_sub(1000)','from __main__ import so_q_sub')
>>> t2 = timeit.Timer('so_q_cat(1000)','from __main__ import so_q_cat')
>>> t1.timeit(number=10000000)
12.166618871951641
>>> t2.timeit(number=10000000)
5.7813972166853773
>>> t1.timeit(number=1)
1.10349...
How do I get an empty array of any size in python?
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241
If by "array" you actually mean a Python list, you can use
a = [0] * 10
or
a = [None] * 10...
Determine the number of NA values in a column
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321
You're over-thinking the problem:
sum(is.na(df$col))
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Switch statement fallthrough in C#?
... 0), or using the special goto case (see case 1) or goto default (see case 2) forms:
switch (/*...*/) {
case 0: // shares the exact same code as case 1
case 1:
// do something
goto case 2;
case 2:
// do something else
goto default;
default:
//...
Python str vs unicode types
Working with Python 2.7, I'm wondering what real advantage there is in using the type unicode instead of str , as both of them seem to be able to hold Unicode strings. Is there any special reason apart from being able to set Unicode codes in unicode strings using the escape char \ ?:
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What's the Android ADB shell “dumpsys” tool and what are its benefits?
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248
What's dumpsys and what are its benefit
dumpsys is an android tool that runs on the device an...
Does Internet Explorer 8 support HTML 5?
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IE8 beta 2 supports two APIs from HTML5: cross-document messaging and non-SQL storage.
IE8 beta 2 doesn’t implement the HTML5 parsing algorithm or the new elements (no <canvas> or <video> support).
There are also bug f...
rmagick gem install “Can't find Magick-config”
...g to install the rmagick gem. I am on Snowleopard 10.6 using RVM, Ruby 1.9.2-head and Rails 3.05. Responses to similar questions recommended installing ImageMagick, which I successfully did. Other suggested installing the "libmagick9-dev library", however, I can not figure out how to do this.
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