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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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Phonegap Cordova installation Windows
...ordova is absolutely horrible. All I'm trying to do is install PhoneGap 3.0 on my Windows environment but having no success.
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What are bitwise operators?
...t's own bit in a bitset (byte, short, int, or long). For example:
Read: 00000001
Write: 00000010
So if you want to pass read AND write, you would pass (READ | WRITE) which then combines the two into
00000011
Which then can be decrypted on the other end like:
if ((flag & Read) != 0) { /...
How do I measure separate CPU core usage for a process?
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Bojin Li
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answered Oct 11 '10 at 21:45
abdollarabdollar
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Are +0 and -0 the same?
Reading through the ECMAScript 5.1 specification , +0 and -0 are distinguished.
9 Answers
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How to add an extra column to a NumPy array
...lution and faster to boot is to do the following:
import numpy as np
N = 10
a = np.random.rand(N,N)
b = np.zeros((N,N+1))
b[:,:-1] = a
And timings:
In [23]: N = 10
In [24]: a = np.random.rand(N,N)
In [25]: %timeit b = np.hstack((a,np.zeros((a.shape[0],1))))
10000 loops, best of 3: 19.6 us per ...
Use CSS3 transitions with gradient backgrounds
...been some browser releases that supported transitions on gradients (e.g IE10. I tested gradient transitions in 2016 in IE and they seemed to work at the time, but my test code no longer works.)
Update: October 2018
Gradient transitions with un-prefixed new syntax [e.g. radial-gradient(...)]now conf...
What's the fastest way to merge/join data.frames in R?
...he first example sqldf is 3x slower than data.table and in the second its 200x faster than plyr and 100 times faster than data.table. Below we show the input code, the output timings for the merge and the output timings for the aggregate. Its also worthwhile noting that sqldf is based on a databa...
Detect URLs in text with JavaScript
... mplungjan
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answered Sep 30 '09 at 20:34
Crescent FreshCrescent Fresh
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How to form tuple column from two columns in Pandas
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Get comfortable with zip. It comes in handy when dealing with column data.
df['new_col'] = li...