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List comprehension in Ruby
...1, 2, 3, 4, 5, 6]
new_array = some_array.comprehend {|x| x * 3 if x % 2 == 0}
puts new_array
Prints:
6
12
18
I would probably just do it the way you did though.
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How to track down a “double free or corruption” error
...
answered May 25 '10 at 8:42
HasturkunHasturkun
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...
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('...
Optional Parameters with C++ Macros
...rd trick to count the number of arguments to a macro.
enum
{
plain = 0,
bold = 1,
italic = 2
};
void PrintString(const char* message, int size, int style)
{
}
#define PRINT_STRING_1_ARGS(message) PrintString(message, 0, 0)
#define PRINT_STRING_2_ARGS(message, size) ...
How to count the number of true elements in a NumPy bool array
...xample:
>>> import numpy as np
>>> boolarr = np.array([[0, 0, 1], [1, 0, 1], [1, 0, 1]], dtype=np.bool)
>>> boolarr
array([[False, False, True],
[ True, False, True],
[ True, False, True]], dtype=bool)
>>> np.sum(boolarr)
5
Of course, that is ...
Why is there no xrange function in Python3?
...pple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s per loop
Now, python.org 3.3.0 64-bit:
In [83]: %timeit collections.deque((x for x in range(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.32 s per loop
...
How to check if an int is a null
...
An int is not null, it may be 0 if not initialized.
If you want an integer to be able to be null, you need to use Integer instead of int.
Integer id;
String name;
public Integer getId() { return id; }
Besides the statement if(person.equals(null)) can...
What's the difference between “groups” and “captures” in .NET regular expressions?
...ew value. Not .NET, which will keep this history and places it in Captures[0].
If we change your regex to look as follows:
MatchCollection matches = Regex.Matches("{Q}{R}{S}", @"(\{[A-Z]\})+");
you will notice that the first Group will have one Captures (the first group always being the whole m...
How can I shrink the drawable on a button?
...rawable = getResources().getDrawable(R.drawable.s_vit);
drawable.setBounds(0, 0, (int)(drawable.getIntrinsicWidth()*0.5),
(int)(drawable.getIntrinsicHeight()*0.5));
ScaleDrawable sd = new ScaleDrawable(drawable, 0, scaleWidth, scaleHeight);
Button btn = findViewbyId(R.id.yo...
Convert RGBA PNG to RGB with PIL
...
130
Here's a version that's much simpler - not sure how performant it is. Heavily based on some djan...