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Making WPF applications look Metro-styled, even in Windows 7? (Window Chrome / Theming / Theme)
...
+100
What I did was creating my own Window and Style. Because I like to have control over everything and I didn't want some external libra...
Is it correct to use JavaScript Array.sort() method for shuffling?
...
110
It's never been my favourite way of shuffling, partly because it is implementation-specific as y...
Extract elements of list at odd positions
...l. 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
Explanation
The [1::2] at the end is just a notation for list slicing. Usually it is in the followi...
Simple Digit Recognition OCR in OpenCV-Python
...r in box.
Once corresponding digit key is pressed, it resizes this box to 10x10 and saves 100 pixel values in an array (here, samples) and corresponding manually entered digit in another array(here, responses).
Then save both the arrays in separate txt files.
At the end of manual classification of...
Where can I find a NuGet package for upgrading to System.Web.Http v5.0.0.0?
Just upgraded an ASP.NET MVC4 project to use Unity.WebApi version 5.0.0.0 and it requires System.Web.Http v 5.0.0.0 as per the following error:
...
while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...ntents of True. In other words, True is reassignable:
Python 2.7 (r27:82508, Jul 3 2010, 21:12:11)
[GCC 4.0.1 (Apple Inc. build 5493)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> True = 4
>>> True
4
In Python 3.x it truly becomes a k...
How do I find out if first character of a string is a number?
...
260
Character.isDigit(string.charAt(0))
Note that this will allow any Unicode digit, not just 0-9....
Converting RGB to grayscale/intensity
...ic weights to channels R, G, and B ought to be applied. These weights are: 0.2989, 0.5870, 0.1140.
8 Answers
...
Append value to empty vector in R?
...et.seed(21)
values <- sample(letters, 1e4, TRUE)
vector <- character(0)
# slow
system.time( for (i in 1:length(values)) vector[i] <- values[i] )
# user system elapsed
# 0.340 0.000 0.343
vector <- character(length(values))
# fast(er)
system.time( for (i in 1:length(values)) vec...
How to filter Pandas dataframe using 'in' and 'not in' like in SQL
...where)
As a worked example:
import pandas as pd
>>> df
country
0 US
1 UK
2 Germany
3 China
>>> countries_to_keep
['UK', 'China']
>>> df.country.isin(countries_to_keep)
0 False
1 True
2 False
3 True
Name: country, dtype: bool
>>>...
