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Simple Digit Recognition OCR in OpenCV-Python
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541
Well, I decided to workout myself on my question to solve above problem. What I wanted is to imp...
Extract elements of list at odd positions
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Solution
Yes, you can:
l = L[1::2]
And this is all. The result will contain the elements placed on the following positions (0-based, so first element is at position 0, second at 1 etc.):
1, 3, 5
so the result (actual numbers) will be:
2, 4, 6
Exp...
How do I find out if first character of a string is a number?
... && c <= '9');
Or the slower regex solutions:
s.substring(0, 1).matches("\\d")
// or the equivalent
s.substring(0, 1).matches("[0-9]")
However, with any of these methods, you must first be sure that the string isn't empty. If it is, charAt(0) and substring(0, 1) will throw a StringIn...
Converting RGB to grayscale/intensity
...nels R, G, and B ought to be applied. These weights are: 0.2989, 0.5870, 0.1140.
8 Answers
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while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
Intrigued by this question about infinite loops in perl: while (1) Vs. for (;;) Is there a speed difference? , I decided to run a similar comparison in python. I expected that the compiler would generate the same byte code for while(True): pass and while(1): pass , but this is actually not the c...
How to take column-slices of dataframe in pandas
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10 Answers
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How to filter Pandas dataframe using 'in' and 'not in' like in SQL
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891
You can use pd.Series.isin.
For "IN" use: something.isin(somewhere)
Or for "NOT IN": ~something....
Append value to empty vector in R?
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212
Appending to an object in a for loop causes the entire object to be copied on every iteration, ...
Tools for analyzing performance of a Haskell program
...learn Haskell (so currently I'm a completly beginner) I came over Problem 12 . I wrote this (naive) solution:
4 Answers
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Delete first character of a string in Javascript
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14 Answers
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