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Selecting pandas column by location
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155
Two approaches that come to mind:
>>> df
A B C D
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Why does changing 0.1f to 0 slow down performance by 10x?
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1627
Welcome to the world of denormalized floating-point! They can wreak havoc on performance!!!
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What is a regular expression which will match a valid domain name without a subdomain?
...ee comments), given your specific requirements:
/^[a-zA-Z0-9][a-zA-Z0-9-]{1,61}[a-zA-Z0-9]\.[a-zA-Z]{2,}$/
But note this will reject a lot of valid domains.
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Type-juggling and (strict) greater/lesser-than comparisons in PHP
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edited May 23 '17 at 11:47
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answered Apr 4 '13 at 14:10
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Find indices of elements equal to zero in a NumPy array
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numpy.where() is my favorite.
>>> x = numpy.array([1,0,2,0,3,0,4,5,6,7,8])
>>> numpy.where(x == 0)[0]
array([1, 3, 5])
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Difference between break and continue statement
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21 Answers
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Phonegap Cordova installation Windows
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13 Answers
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What are bitwise operators?
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Since nobody has broached the subject of why these are useful:
I use bitwise operations a lot...
How to add an extra column to a NumPy array
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How do I measure separate CPU core usage for a process?
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You can still do this in top. While top is running, press '1' on your keyboard, it will then ...