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Removing duplicates in lists
...ample should cover whatever you are trying to do:
>>> t = [1, 2, 3, 1, 2, 5, 6, 7, 8]
>>> t
[1, 2, 3, 1, 2, 5, 6, 7, 8]
>>> list(set(t))
[1, 2, 3, 5, 6, 7, 8]
>>> s = [1, 2, 3]
>>> list(set(t) - set(s))
[8, 5, 6, 7]
As you can see from the example resu...
Syntax for creating a two-dimensional array
...ti[0] = new int[10];
multi[1] = new int[10];
multi[2] = new int[10];
multi[3] = new int[10];
multi[4] = new int[10];
Note that every element will be initialized to the default value for int, 0, so the above are also equivalent to:
int[][] multi = new int[][]{
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
...
Why exactly is eval evil?
...tors:
(let ((ops '(+ *)))
(dolist (op ops)
(print (eval (list op 1 2 3)))))
That's better written as:
(let ((ops '(+ *)))
(dolist (op ops)
(print (funcall op 1 2 3))))
There are lots of examples where beginners learning Lisp think they need EVAL, but they don't need it - since expressi...
Is 'float a = 3.0;' a correct statement?
...
It is not an error to declare float a = 3.0 : if you do, the compiler will convert the double literal 3.0 to a float for you.
However, you should use the float literals notation in specific scenarios.
For performance reasons:
Specifically, consider:
float fo...
What does the “map” method do in Ruby?
...
432
The map method takes an enumerable object and a block, and runs the block for each element, out...
Dealing with multiple Python versions and PIP?
...
23 Answers
23
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jQuery map vs. each
...you can potentially waste a lot of memory.
For example:
var items = [1,2,3,4];
$.each(items, function() {
alert('this is ' + this);
});
var newItems = $.map(items, function(i) {
return i + 1;
});
// newItems is [2,3,4,5]
You can also use the map function to remove an item from an array. F...
Could not find com.google.android.gms:play-services:3.1.59 3.2.25 4.0.30 4.1.32 4.2.40 4.2.42 4.3.23
...
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edited Dec 3 '15 at 1:20
CJBS
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a...
Get: TypeError: 'dict_values' object does not support indexing when using python 3.2.3 [duplicate]
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3 Answers
3
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