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What is the easiest way to push an element to the beginning of the array?
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390
What about using the unshift method?
ary.unshift(obj, ...) → ary
Prepends objects to the...
Bitwise operation and usage
...bit at a time.
AND is 1 only if both of its inputs are 1, otherwise it's 0.
OR is 1 if one or both of its inputs are 1, otherwise it's 0.
XOR is 1 only if exactly one of its inputs are 1, otherwise it's 0.
NOT is 1 only if its input is 0, otherwise it's 0.
These can often be best shown as truth ...
CSS - Overflow: Scroll; - Always show vertical scroll bar?
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401
Just ran into this problem myself. OSx Lion hides scrollbars while not in use to make it seem m...
How can I force division to be floating point? Division keeps rounding down to 0?
... I want to calculate a / b , so if I use integer division I'll always get 0 with a remainder of a .
11 Answers
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Best way to test if a row exists in a MySQL table
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edited Sep 4 '19 at 19:20
SovietFrontier
1,5441010 silver badges2727 bronze badges
answered Nov 4 '09 ...
How do I get my Python program to sleep for 50 milliseconds?
How do I get my Python program to sleep for 50 milliseconds?
6 Answers
6
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Hex representation of a color with alpha channel?
...se rgba() functional notation with decimals or percentages, e.g. rgba(255, 0, 0, 0.5) would be 50% transparent red. RGB channels are 0-255 or 0%-100%, alpha is 0-1.
In CSS 4*, you can specify the alpha channel using the 7th and 8th characters of an 8 digit hex colour, or 4th character of a 4 digit ...
What is the Difference Between read() and recv() , and Between send() and write()?
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130
The difference is that recv()/send() work only on socket descriptors and let you specify certain...
On localhost, how do I pick a free port number?
...do I figure out which port is available? I assume I cannot listen on port 80 or 21?
5 Answers
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How to access pandas groupby dataframe by key
...group method:
In [21]: gb.get_group('foo')
Out[21]:
A B C
0 foo 1.624345 5
2 foo -0.528172 11
4 foo 0.865408 14
Note: This doesn't require creating an intermediary dictionary / copy of every subdataframe for every group, so will be much more memory-efficient that creating...