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Returning first x items from array
...ray_slice returns a slice of an array
$sliced_array = array_slice($array, 0, 5)
is the code you want in your case to return the first five elements
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What are “named tuples” in Python?
...xcept that they are immutable. They were added in Python 2.6 and Python 3.0, although there is a recipe for implementation in Python 2.4.
For example, it is common to represent a point as a tuple (x, y). This leads to code like the following:
pt1 = (1.0, 5.0)
pt2 = (2.5, 1.5)
from math import s...
Underscore: sortBy() based on multiple attributes
...dArray = _(patients).chain().sortBy(function(patient) {
return patient[0].name;
}).sortBy(function(patient) {
return patient[0].roomNumber;
}).value();
When the second sortBy finds that John and Lisa have the same room number it will keep them in the order it found them, which the first so...
Is there an expression for an infinite generator?
...gument iter = zero-argument callable + sentinel value
int() always returns 0
Therefore, iter(int, 1) is an infinite iterator. There are obviously a huge number of variations on this particular theme (especially once you add lambda into the mix). One variant of particular note is iter(f, object()),...
Share Large, Read-Only Numpy Array Between Multiprocessing Processes
I have a 60GB SciPy Array (Matrix) I must share between 5+ multiprocessing Process objects. I've seen numpy-sharedmem and read this discussion on the SciPy list. There seem to be two approaches-- numpy-sharedmem and using a multiprocessing.RawArray() and mapping NumPy dtype s to ctype s. ...
Is there XNOR (Logical biconditional) operator in C#?
...te also that this doesn't generalize to bitwise operations, where you want 0x1234 XNOR 0x5678 == 0xFFFFBBB3 (assuming 32 bits). For that, you need to build up from other operations, like ~(A^B). (Note: ~, not !.)
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Capitalize only first character of string and leave others alone? (Rails)
... that the only letter changed is the first one.
new_string = string.slice(0,1).capitalize + string.slice(1..-1)
Update:
irb(main):001:0> string = "i'm from New York..."
=> "i'm from New York..."
irb(main):002:0> new_string = string.slice(0,1).capitalize + string.slice(1..-1)
=> "I'm ...
Is there a way to measure how sorted a list is?
...onsider the example sequence 9, 5, 7, 6. This sequence has the inversions (0,1), (0,2), (0,3), (2,3) and the inversion number 4.
If you want a value between 0 and 1, you can divide the inversion number by N choose 2.
To actually create an algorithm to compute this score for how sorted a list is, you...
How do I check which version of NumPy I'm using?
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David Stansby
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answered Oct 5 '09 at 14:02
SilentGhostSilentGhost
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How do I measure execution time of a command on the Windows command line?
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