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Aggregate / summarize multiple variables per group (e.g. sum, mean)
...~ variable, sum)
# year month x1 x2
1 2000 1 -80.83405 -224.9540159
2 2000 2 -223.76331 -288.2418017
3 2000 3 -188.83930 -481.5601913
4 2000 4 -197.47797 -473.7137420
5 2000 5 -259.07928 -372.4563522
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How to create a tuple with only one element
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Unique combination of all elements from two (or more) vectors
... expand.grid(a,b)
Var1 Var2
1 ABC 2012-05-01
2 DEF 2012-05-01
3 GHI 2012-05-01
4 ABC 2012-05-02
5 DEF 2012-05-02
6 GHI 2012-05-02
7 ABC 2012-05-03
8 DEF 2012-05-03
9 GHI 2012-05-03
10 ABC 2012-05-04
11 DEF 2012-05-04
12 GHI 2012-05-04
13 ABC 2012-05-05
14 DEF 2012-05-...
How do I check the operating system in Python?
...2":
# linux
elif platform == "darwin":
# OS X
elif platform == "win32":
# Windows...
sys.platform has finer granularity than sys.name.
For the valid values, consult the documentation.
See also the answer to “What OS am I running on?”
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jquery-ui sortable | How to get it work on iPad/touchdevices?
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Extension methods cannot be dynamically dispatched
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Why is rbindlist “better” than rbind?
...d will join by position
eg
do.call(rbind, list(data.frame(a = 1:2, b = 2:3), data.frame(b = 1:2, a = 2:3)))
## a b
## 1 1 2
## 2 2 3
## 3 2 1
## 4 3 2
rbindlist(list(data.frame(a = 1:5, b = 2:6), data.frame(b = 1:5, a = 2:6)))
## a b
## 1: 1 2
## 2: 2 3
## 3: 1 2
## 4: 2 3
Some...
Get specific ArrayList item
How can I get a specific item from this ArrayList ? mainList[3] ?
8 Answers
8
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How does one reorder columns in a data frame?
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Your dataframe has four columns like so df[,c(1,2,3,4)].
Note the first comma means keep all t...
How to expand/collapse a diff sections in Vimdiff?
...e expand/collapse a diff section, have full file expansion/only diffs with 3 context lines above or below, etc.). I currently know only the following commands :
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