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Can I use `pip` instead of `easy_install` for `python setup.py install` dependency resolution?
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How to create a tuple with only one element
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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 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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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-...
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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Get specific ArrayList item
How can I get a specific item from this ArrayList ? mainList[3] ?
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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...
Dynamically select data frame columns using $ and a character value
... a reproducible example below:
# set seed for reproducibility
set.seed(123)
df <- data.frame( col1 = sample(5,10,repl=T) , col2 = sample(5,10,repl=T) , col3 = sample(5,10,repl=T) )
# We want to sort by 'col3' then by 'col1'
sort_list <- c("col3","col1")
# Use 'do.call' to call order. Sec...