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Split delimited strings in a column and insert as new rows [duplicate]
...her way of doing it..
df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F)
df
## V1 V2
## 1 1 a,b,c
## 2 2 a,c
## 3 3 b,d
## 4 4 e,f
s <- strsplit(df$V2, split = ",")
data.frame(V1 = rep(df$V1, sapply(s, length)), V2 = ...
do N times (declarative syntax)
..., without any library, just native vanilla.
To basically call something() 3 times, use:
[1,2,3].forEach(function(i) {
something();
});
considering the following function:
function something(){ console.log('something') }
The outpout will be
something
something
something
To complete thi...
Using python map and other functional tools
...ferent functions, but to access it directly from maptest:
foos = [1.0,2.0,3.0,4.0,5.0]
bars = [1,2,3]
def maptest(foo):
print foo, bars
map(maptest, foos)
With your original maptest function you could also use a lambda function in map:
map((lambda foo: maptest(foo, bars)), foos)
...
Printing tuple with string formatting in Python
So, i have this problem.
I got tuple (1,2,3) which i should print with string formatting.
eg.
14 Answers
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Can dplyr package be used for conditional mutating?
... 1 & b == 4), 2,
ifelse(a == 0 | a == 1 | a == 4 | a == 3 | c == 4, 3, NA)))
Added - if_else: Note that in dplyr 0.5 there is an if_else function defined so an alternative would be to replace ifelse with if_else; however, note that since if_else is stricter than ifelse (both leg...
Need a simple explanation of the inject method
... |
edited Apr 2 '09 at 16:37
answered Apr 2 '09 at 16:31
Dr...
Numpy: Divide each row by a vector element
...
answered Oct 26 '13 at 2:38
JoshAdelJoshAdel
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Programmatically obtain the Android API level of a device?
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Vivek
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answered Nov 2 '14 at 11:01
Arkadiusz Cieślińsk...
How to insert element into arrays at specific position?
...
23 Answers
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Operation on every pair of element in a list
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233
Check out product() in the itertools module. It does exactly what you describe.
import iterto...