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What is a regular expression for a MAC Address?
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The standard (IEEE 802) format for
printing MAC-48 addresses in
human-friendly form is six groups of
two hexadecimal digits, separated by
hyphens - or colons :.
So:
^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})$
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WPF ToolBar: how to remove grip and overflow
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answered Jun 26 '09 at 20:57
rmoorermoore
14.2k44 gold badges5656 silver badges5959 bronze badges
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Pandas dataframe get first row of each group
...column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6 first
6 7 fourth
To get n first records, you can use head():
>>> df.groupby('id').head(2).reset_index(drop=True)
id value
0 ...
How to fix the uninitialized constant Rake::DSL problem on Heroku?
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205
Put this in your Rakefile above require 'rake':
require 'rake/dsl_definition'
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How can I autoplay a video using the new embed code style for Youtube?
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+50
Just put "?autoplay=1" in the url the video will autoload.
So your url would be:
http://www.youtube.com/embed/JW5meKfy3fY?autoplay=1
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how to rotate a bitmap 90 degrees
There is a statement in android canvas.drawBitmap(visiblePage, 0, 0, paint);
10 Answers
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Principal component analysis in Python
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edited Sep 3 '10 at 11:40
nikow
19.6k66 gold badges4242 silver badges6969 bronze badges
answe...
Is there an equivalent to e.PageX position for 'touchstart' event as there is for click event?
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180
Kinda late, but you need to access the original event, not the jQuery massaged one. Also, since...
Can dplyr package be used for conditional mutating?
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220
Use ifelse
df %>%
mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 1 & b == 4), 2,
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How do I use vim registers?
... D. Ben Knoble
3,47211 gold badge1717 silver badges3030 bronze badges
answered Sep 30 '09 at 13:12
FModa3FModa3
12.7k11 gold badge...