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Counting array elements in Python [duplicate]
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Especially when both of us mentioned that is was bad form. Understanding what length "really" does is important in it's own right.
– Gregg Lind
Oct 14 '08 at 17:11
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Counting the number of option tags in a select tag in jQuery
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You can use either length property and length is better on performance than size.
$('#input1 option').length;
OR you can use size function like (removed in jQuery v3)
$('#input1 option').size();
$(document).ready(function(){
console.log($('#input1 option').size());
console....
LINQ with groupby and count
...set of
<DATA> | Grouping Key (x=>x.metric) |
joe 1 01/01/2011 5 | 1
jane 0 01/02/2011 9 | 0
john 2 01/03/2011 0 | 2
jim 3 01/04/2011 1 | 3
jean 1 01/05/2011 3 | 1
jill 2 01/06/2011 5 | 2
jeb 0 01/07/2011 3 | 0
jenn 0 01/08/2011 7 | 0
it would result in the followin...
Filtering Pandas DataFrames on dates
...l based indexing or .iloc for positional indexing.
For example:
df.loc['2014-01-01':'2014-02-01']
See details here http://pandas.pydata.org/pandas-docs/stable/dsintro.html#indexing-selection
If the column is not the index you have two choices:
Make it the index (either temporarily or permanen...
How to select the last record of a table in SQL?
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Without any further information, which Database etc the best we can do is something like
Sql Server
SELECT TOP 1 * FROM Table ORDER BY ID DESC
MySql
SELECT * FROM Table ORDER BY ID DESC LIMIT 1
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Python style - line continuation with strings? [duplicate]
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The problem is when assigning to a variable, this form looks too similar to a tuple. If you add a comma between the strings, it's a tuple with two strings.
– Eric
Mar 23 '19 at 1:41
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Recommended way to insert elements into map [duplicate]
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assert( myMap.find( key )->second == value ); // post-condition
This form will overwrite any existing entry.
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Sorting 1 million 8-decimal-digit numbers with 1 MB of RAM
...ink the key observation is that an 8-digit number has about 26.6 bits of information and one million is 19.9 bits. If you delta compress the list (store the differences of adjacent values) the differences range from 0 (0 bits) to 99999999 (26.6 bits) but you can't have the maximum delta between eve...
CMake not able to find OpenSSL library
... Works like a charm, thanks! I was able to extract the zip file downloaded form the link you mentioned. After that I just added -DOPENSSL_ROOT-DIR="C:/Path/To/Extracted/Files".
– Charlie Vieillard
Apr 9 '15 at 8:05
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Git and Mercurial - Compare and Contrast
...sions (plugins) and established API; Git has scriptability and established formats.
There are a few things that differ Mercurial from Git, but there are other things that make them similar. Both projects borrow ideas from each other. For example hg bisect command in Mercurial (formerly bisect ex...