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How can I count the occurrences of a list item?
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If you only want one item's count, use the count method:
>>> [1, 2, 3, 4, 1, 4, 1].count(1)
3
Don't use this if you want to count multiple items. Calling count in a loop requires a separate pass over the list for ...
How to use LINQ to select object with minimum or maximum property value
... do you do the superfluous check curMin == null? curMin could only be null if you were using Aggregate() with a seed that is null.
– Good Night Nerd Pride
May 18 '16 at 13:01
6
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jQuery date formatting
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@Dotnet if it could be done using jQuery, there would not be a jQuery plug-in for date formatting, would there?
– Pekka
Mar 9 '11 at 18:32
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Best way to allow plugins for a PHP application
...eners;
$num_args = func_num_args();
$args = func_get_args();
if($num_args < 2)
trigger_error("Insufficient arguments", E_USER_ERROR);
// Hook name should always be first argument
$hook_name = array_shift($args);
if(!isset($listeners[$hook_name]))
return...
Convert a float64 to an int in Go
... Such casts have a problem in Go that can be unexpected (at least if you come from Java): "In all non-constant conversions involving floating-point or complex values, if the result type cannot represent the value the conversion succeeds but the result value is implementation-dependent." (go...
Java: Detect duplicates in ArrayList?
...into a Set (using the Set(Collection) constructor or Set.addAll), then see if the Set has the same size as the ArrayList.
List<Integer> list = ...;
Set<Integer> set = new HashSet<Integer>(list);
if(set.size() < list.size()){
/* There are duplicates */
}
Update: If I'm un...
What does SQL clause “GROUP BY 1” mean?
...first column in select statement which is
account_id.
You also can specify in ORDER BY.
Note : The number in ORDER BY and GROUP BY always start with 1 not with 0.
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Python Dictionary Comprehension
...n't use them to add keys to an existing dictionary. Also, you have to specify the keys and values, although of course you can specify a dummy value if you like.
>>> d = {n: n**2 for n in range(5)}
>>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
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How to initialize a private static const map in C++?
...;< A::myMap[1]; into main(). It gives an error. The error doesn't occur if I remove the const qualifiers, so I guess map's operator[] can't handle a const map, at least, not in the g++ implementation of the C++ library.
– Craig McQueen
Oct 31 '13 at 1:08
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How can I check for an empty/undefined/null string in JavaScript?
I saw this question , but I didn't see a JavaScript specific example. Is there a simple string.Empty available in JavaScript, or is it just a case of checking for "" ?
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