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How to find list intersection?
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answered Sep 13 '10 at 1:32
Mark ByersMark Byers
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How to increase the gap between text and underlining in CSS
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370
No, but you could go with something like border-bottom: 1px solid #000 and padding-bottom: 3px.
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how does multiplication differ for NumPy Matrix vs Array classes?
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Neil G
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answered Oct 8 '10 at 16:49
Joe KingtonJoe Ki...
How to profile a bash shell script slow startup?
... you'd like to begin a trace in any Bash script):
PS4='+ $(date "+%s.%N")\011 '
exec 3>&2 2>/tmp/bashstart.$$.log
set -x
add
set +x
exec 2>&3 3>&-
at the end of ~/.bashrc (or at the end of the section of any Bash script you'd like tracing to stop). The \011 is an octal ...
Why are these numbers not equal?
...cially true because some values which are simple, finite decimals (such as 0.1 and 0.05) are not represented exactly in the computer and so the results of arithmetic on them may not give a result that is identical to a direct representation of the "known" answer.
This is a well known limitation of ...
Regular expression for matching HH:MM time format
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Your original regular expression has flaws: it wouldn't match 04:00 for example.
This may work better:
^([0-1]?[0-9]|2[0-3]):[0-5][0-9]$
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Apply multiple functions to multiple groupby columns
...f = pd.DataFrame(np.random.rand(4,4), columns=list('abcd'))
df['group'] = [0, 0, 1, 1]
df
a b c d group
0 0.418500 0.030955 0.874869 0.145641 0
1 0.446069 0.901153 0.095052 0.487040 0
2 0.843026 0.936169 0.926090 0.041722 1
3 0.635846 ...
Context switches much slower in new linux kernels
We are looking to upgrade the OS on our servers from Ubuntu 10.04 LTS to Ubuntu 12.04 LTS. Unfortunately, it seems that the latency to run a thread that has become runnable has significantly increased from the 2.6 kernel to the 3.2 kernel. In fact the latency numbers we are getting are hard to belie...
Twitter's typeahead.js suggestions are not styled (have no border, transparent background, etc.)
I'm using twitter's typeahead.js 0.9.3 and it seems my suggestions are not styled at all.
9 Answers
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Find MongoDB records where array field is not empty
... the key, you can use:
ME.find({ pictures: { $exists: true, $not: {$size: 0} } })
MongoDB don't use indexes if $size is involved, so here is a better solution:
ME.find({ pictures: { $exists: true, $ne: [] } })
Since MongoDB 2.6 release, you can compare with the operator $gt but could lead to u...