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How to add an extra column to a NumPy array
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I think a more straightforward solution 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.hstac...
Memoization in Haskell?
...f :: Int -> Int
faster_f n = f_list !! n
That performs passably well, and replaces what was going to take O(n^3) time with something that memoizes the intermediate results.
But it still takes linear time just to index to find the memoized answer for mf. This means that results like:
*Main Dat...
Checking if a string can be converted to float in Python
I've got some Python code that runs through a list of strings and converts them to integers or floating point numbers if possible. Doing this for integers is pretty easy
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Cycles in family tree software
I am the developer of some family tree software (written in C++ and Qt). I had no problems until one of my customers mailed me a bug report. The problem is that the customer has two children with their own daughter, and, as a result, he can't use my software because of errors.
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What do hjust and vjust do when making a plot using ggplot?
...lot using ggplot, I spend a little while trying different values for hjust and vjust in a line like
2 Answers
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SQL JOIN and different types of JOINs
What is a SQL JOIN and what are different types?
6 Answers
6
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NumPy: function for simultaneous max() and min()
numpy.amax() will find the max value in an array, and numpy.amin() does the same for the min value. If I want to find both max and min, I have to call both functions, which requires passing over the (very big) array twice, which seems slow.
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Google Maps API 3 - Custom marker color for default (dot) marker
I've seen lots of other questions similar to this ( here , here and here ), but they all have accepted answers that don't solve my problem. The best solution I have found to the problem is the StyledMarker library, which does let you define custom colours for markers, but I can't get it to use ...
What causes imported Maven project in Eclipse to use Java 1.5 instead of Java 1.6 by default and how
I imported a Maven project and it used Java 1.5 even though I have 1.6 configured as my Eclipse default Preferences->Java->Installed JREs .
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How can I sharpen an image in OpenCV?
... Wikipedia article on unsharp masking:
You use a Gaussian smoothing filter and subtract the smoothed version from the original image (in a weighted way so the values of a constant area remain constant).
To get a sharpened version of frame into image: (both cv::Mat)
cv::GaussianBlur(frame, image, cv:...