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Relationship between SciPy and NumPy
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Last time I checked it, the scipy __init__ method executes a
from numpy import *
so that the whole numpy namespace is included into scipy when the scipy module is imported.
The log10 behavior you are describing is interesting, because both versions are coming from numpy. One is a uf...
Why does the month argument range from 0 to 11 in JavaScript's Date constructor?
... using the below call, I found out that the month argument counts starting from zero.
8 Answers
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Pandas: drop a level from a multi-level column index?
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You can use MultiIndex.droplevel:
>>> cols = pd.MultiIndex.from_tuples([("a", "b"), ("a", "c")])
>>> df = pd.DataFrame([[1,2], [3,4]], columns=cols)
>>> df
a
b c
0 1 2
1 3 4
[2 rows x 2 columns]
>>> df.columns = df.columns.droplevel()
>>...
How can I convert an RGB image into grayscale in Python?
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How about doing it with Pillow:
from PIL import Image
img = Image.open('image.png').convert('LA')
img.save('greyscale.png')
Using matplotlib and the formula
Y' = 0.2989 R + 0.5870 G + 0.1140 B
you could do:
import numpy as np
import matplotlib.pypl...
JS Client-Side Exif Orientation: Rotate and Mirror JPEG Images
...efore actually uploading it. The demo does neither. It simply takes a file from a file input and displays it the right way, when is this useful in the real world? When I parse my page and feed the URLs from the image tags into the loadImage library there is no exif data so can't do that. For the upl...
How do I install an R package from source?
...o try it. However, the first step is to installed a package called RJSONIO from source.
6 Answers
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Determine distance from the top of a div to top of window with javascript
...elementOffset - scrollTop);
The distance variable now holds the distance from the top of the #my-element element and the top-fold.
Here is a demo: http://jsfiddle.net/Rxs2m/
Note that negative values mean that the element is above the top-fold.
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Generate a random point within a circle (uniformly)
...es simply by picking an angle theta. So we now need to generate a distance from the center by picking a point in the sliver ABC. Again, extend to ABCD, where D is now twice the radius from the circle center.
Picking a random point in ABCD is easy using the above method. Pick a random point on AB. U...
Sort points in clockwise order?
...* (a.y - center.y)
if the result is zero, then they are on the same line from the center, if it's positive or negative, then it is on one side or the other, so one point will precede the other.
Using it you can construct a less-than relation to compare points and determine the order in which they ...
What is the most efficient way of finding all the factors of a number in Python?
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from functools import reduce
def factors(n):
return set(reduce(list.__add__,
([i, n//i] for i in range(1, int(n**0.5) + 1) if n % i == 0)))
This will return all of the factors, very quickly, of a n...