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What exactly are iterator, iterable, and iteration?
...aking each item of something, one after another. Any time you use a loop, explicit or implicit, to go over a group of items, that is iteration.
In Python, iterable and iterator have specific meanings.
An iterable is an object that has an __iter__ method which returns an iterator, or which defines ...
Getting output of system() calls in Ruby
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I'd like to expand & clarify chaos's answer a bit.
If you surround your command with backticks, then you don't need to (explicitly) call system() at all. The backticks execute the command and return the output as a string. You can th...
What is the purpose of the : (colon) GNU Bash builtin?
...r than true for portability to ancient Bourne-derived shells. As a simple example, consider having neither the ! pipeline operator nor the || list operator (as was the case for some ancient Bourne shells). This leaves the else clause of the if statement as the only means for branching based on exit ...
Numpy - add row to array
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What is X? If it is a 2D-array, how can you then compare its row to a number: i < 3?
EDIT after OP's comment:
A = array([[0, 1, 2], [0, 2, 0]])
X = array([[0, 1, 2], [1, 2, 0], [2, 1, 2], [3, 2, 0]])
add to A all rows from X w...
asp.net mvc: why is Html.CheckBox generating an additional hidden input
I just noticed that Html.CheckBox("foo") generates 2 inputs instead of one, anybody knows why is this so ?
10 Answers
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What is the difference between the GNU Makefile variable assignments =, ?=, := and +=?
Can anybody give a clear explanation of how variable assignment really works in Makefiles.
6 Answers
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In Python, how do I create a string of n characters in one line of code?
...haracters in Python. Is there a one line answer to achieve this with the existing Python library? For instance, I need a string of 10 letters:
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What is the most efficient way to concatenate N arrays?
...e way to go for convenience and likely performance.
var a = [1, 2], b = ["x", "y"], c = [true, false];
var d = a.concat(b, c);
console.log(d); // [1, 2, "x", "y", true, false];
For concatenating just two arrays, the fact that push accepts multiple arguments consisting of elements to add to the ar...
What's the point of map in Haskell, when there is fmap?
...ical purposes has been part of the Haskell community since before Haskell existed, cf. A History of Haskell, so the comment in question is not in any way second-hand hearsay!
– C. A. McCann
Jul 26 '11 at 21:37
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.NET console application as Windows service
...t which could run as console application or as windows service if run for example from command line using switches.
10 Ans...