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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
...le(a = c(1, 2), b = c(11, 12))
newDT <- DT
.Internal(inspect(DT))
# @0000000003B7E2A0 19 VECSXP g0c7 [OBJ,NAM(2),ATT] (len=2, tl=100)
# @00000000040C2288 14 REALSXP g0c2 [NAM(2)] (len=2, tl=0) 1,2
# @00000000040C2250 14 REALSXP g0c2 [NAM(2)] (len=2, tl=0) 11,12
# ATTRIB: # ..snip..
.Inte...
Returning a boolean from a Bash function
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How can I brew link a specific version?
...ame package in /usr/local/Cellar/libfoo like /usr/local/Cellar/libfoo/1.0.1 , /usr/local/Cellar/libfoo/HEAD and /usr/local/Cellar/libfoo/mycopy
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Ruby Bundle Symbol not found: _SSLv2_client_method (LoadError)
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Finding quaternion representing the rotation from one vector to another
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answered Jul 23 '09 at 14:04
Polaris878Polaris878
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How to get overall CPU usage (e.g. 57%) on Linux [closed]
...ke a look at cat /proc/stat
grep 'cpu ' /proc/stat | awk '{usage=($2+$4)*100/($2+$4+$5)} END {print usage "%"}'
EDIT please read comments before copy-paste this or using this for any serious work. This was not tested nor used, it's an idea for people who do not want to install a utility or for so...
How can I implode an array while skipping empty array items?
...ode('-', array_filter($array));
Obviously this will not work if you have 0 (or any other value that evaluates to false) in your array and you want to keep it. But then you can provide your own callback function.
share
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How do I create a dictionary with keys from a list and values defaulting to (say) zero? [duplicate]
I have a = [1,2,3,4] and I want d = {1:0, 2:0, 3:0, 4:0}
5 Answers
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Rename specific column(s) in pandas
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A much faster implementation would be to use list-comprehension if you need to rename a single c...