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Why does one hot encoding improve machine learning performance?
...h" and "US". Assume, without loss of generality, that these are encoded as 0, 1 and 2. You then have a weight w for this feature in a linear classifier, which will make some kind of decision based on the constraint w×x + b > 0, or equivalently w×x < b.
The problem now is that the weight w c...
How to change line width in ggplot?
... theme(axis.text.x = element_text(
colour = 'black', angle = 90, size = 13,
hjust = 0.5, vjust = 0.5),axis.title.x=element_blank()) +
ylab("FSI (%Change)") +
theme(axis.text.y = element_text(colour = 'black', size = 12),
axis.title.y = element_text(size = 12...
Accessing class variables from a list comprehension in the class definition
...owing will fail:
class A:
a = 42
b = list(a + i for i in range(10))
So, to summarize: you cannot access the class scope from functions, list comprehensions or generator expressions enclosed in that scope; they act as if that scope does not exist. In Python 2, list comprehensions were i...
Checking images for similarity with OpenCV
...ue (maybe a percentage) that indicates how similar these images are? E.g. 100% would be returned if the same image was passed twice, 0% would be returned if the images were totally different.
...
Array.Copy vs Buffer.BlockCopy
...|
edited Feb 15 '17 at 12:09
Ajay
16.3k99 gold badges4646 silver badges9090 bronze badges
answered Sep 7...
Set Colorbar Range in matplotlib
...port matplotlib.pyplot as plt
import numpy as np
cdict = {
'red' : ( (0.0, 0.25, .25), (0.02, .59, .59), (1., 1., 1.)),
'green': ( (0.0, 0.0, 0.0), (0.02, .45, .45), (1., .97, .97)),
'blue' : ( (0.0, 1.0, 1.0), (0.02, .75, .75), (1., 0.45, 0.45))
}
cm = m.colors.LinearSegmentedColormap('...
How To: Best way to draw table in console app (C#)
...ring text, int width)
{
text = text.Length > width ? text.Substring(0, width - 3) + "..." : text;
if (string.IsNullOrEmpty(text))
{
return new string(' ', width);
}
else
{
return text.PadRight(width - (width - text.Length) / 2).PadLeft(width);
}
}
...
[] and {} vs list() and dict(), which is better?
...s/dicts:
>>> from timeit import timeit
>>> timeit("[]")
0.040084982867934334
>>> timeit("list()")
0.17704233359267718
>>> timeit("{}")
0.033620194745424214
>>> timeit("dict()")
0.1821558326547077
and for non-empty:
>>> timeit("[1,2,3]")
0.243...
Too many 'if' statements?
...
600
If you cannot come up with a formula, you can use a table for such a limited number of outcomes...
How does numpy.histogram() work?
...qual width) of each bar.
In this example:
np.histogram([1, 2, 1], bins=[0, 1, 2, 3])
There are 3 bins, for values ranging from 0 to 1 (excl 1.), 1 to 2 (excl. 2) and 2 to 3 (incl. 3), respectively. The way Numpy defines these bins if by giving a list of delimiters ([0, 1, 2, 3]) in this example...