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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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fol...
How to check whether a file is empty or not?
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edited Dec 7 '14 at 21:22
Achal Dave
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Relative frequencies / proportions with dplyr
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mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes it easy to prog...
Python “SyntaxError: Non-ASCII character '\xe2' in file”
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147
You've got a stray byte floating around. You can find it by running
with open("x.py") as fp:
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How to implement common bash idioms in Python? [closed]
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144
votes
Any shell has several sets of features.
The Essential Linux/Unix commands. ...
What are the differences between type() and isinstance()?
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All Workers Are Essential
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answered Oct 11 '09 at 4:31
Alex MartelliA...
Try-catch speeding up my code?
... Lightness Races in Orbit
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answered Jan 20 '12 at 20:14
Eric LippertEric Lippert
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C# Double - ToString() formatting with two decimal places but no rounding
...Truncate(myDoubleValue * 100) / 100;
For instance:
If the number is 50.947563 and you use the following, the following will happen:
- Math.Truncate(50.947563 * 100) / 100;
- Math.Truncate(5094.7563) / 100;
- 5094 / 100
- 50.94
And there's your answer truncated, now to format the string simply ...
Taking screenshot on Emulator from Android Studio
...f you keep the emulator in Android Studio as possible since Android Studio 4.1 click here to save the screenshot in your standard location:
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Most lightweight way to create a random string and a random hexadecimal number
...d t2 as above:
>>> t1 = timeit.Timer("''.join(random.choice('0123456789abcdef') for n in xrange(30))", "import random")
>>> t2 = timeit.Timer("binascii.b2a_hex(os.urandom(15))", "import os, binascii")
>>> t3 = timeit.Timer("'%030x' % random.randrange(16**30)", "import ran...