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Why dict.get(key) instead of dict[key]?
...ry.get("bogus") returns a value which evaluates to False in a boolean context (i.e. a Falsey value), such as 0 or an empty string, '', then dictionary.get("bogus") or my_default would evaluate to my_default whereas dictionary.get("bogus", my_default) would return the Falsey value. So no, dictionary....
How to comment out a block of Python code in Vim
...habh-manocha: use visual block (Ctrl-V) to select all the added # and type x to delete them.
– theosp
Apr 1 '10 at 16:18
3
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Checking to see if one array's elements are in another array in PHP
...s then why in PHP docs about this function they say "Returns FALSE if var exists and has a non-empty, non-zero value. Otherwise returns TRUE. The following things are considered to be empty: array() (an empty array)"? Source: php.net/manual/en/function.empty.php
– Pere
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How to avoid using Select in Excel VBA
I've heard much about the understandable abhorrence of using .Select in Excel VBA, but am unsure of how to avoid using it. I am finding that my code would be more re-usable if I were able to use variables instead of Select functions. However, I am not sure how to refer to things (like the Activ...
How to compile a static library in Linux?
I have a question: How to compile a static library in Linux with gcc , i.e. I need to compile my source code into a file named out.a. Is it sufficient to simply compile with the command gcc -o out.a out.c ? I'm not quite familiar with gcc , hope anyone can give me a hand.
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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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