大约有 47,000 项符合查询结果（耗时：0.0420秒） [XML]
How to generate all permutations of a list?
...
33 Answers
33
Active
...
Fastest way to list all primes below N
...
35 Answers
35
Active
...
Mean per group in a data.frame [duplicate]
....table(text=
'Name Month Rate1 Rate2
Aira 1 12 23
Aira 2 18 73
Aira 3 19 45
Ben 1 53 19
Ben 2 22 87
Ben 3 19 45
Cat 1 22 87
Cat 2 67 43
Cat ...
How can I delete one element from an array by value
...
I think I've figured it out:
a = [3, 2, 4, 6, 3, 8]
a.delete(3)
#=> 3
a
#=> [2, 4, 6, 8]
share
|
improve this answer
|
follow
...
“Cloning” row or column vectors
...
83
Here's an elegant, Pythonic way to do it:
>>> array([[1,2,3],]*3)
array([[1, 2, 3],
...
How to remove a key from Hash and get the remaining hash in Ruby/Rails?
...
answered Jun 19 '12 at 17:03
Peter BrownPeter Brown
48k1616 gold badges103103 silver badges140140 bronze badges
...
What's the difference between tilde(~) and caret(^) in package.json?
...
4053
See the NPM docs and semver docs:
~version “Approximately equivalent to version”, will upda...
For each row return the column name of the largest value
...amples using sample reproducible):
DF <- data.frame(V1=c(2,8,1),V2=c(7,3,5),V3=c(9,6,4))
colnames(DF)[apply(DF,1,which.max)]
[1] "V3" "V1" "V2"
A faster solution than using apply might be max.col:
colnames(DF)[max.col(DF,ties.method="first")]
#[1] "V3" "V1" "V2"
...where ties.method can be...
Does assignment with a comma work?
Why does aaa = 1,2,3 work and set the value of aaa to 1 ?
4 Answers
4
...
How do you rotate a two dimensional array?
...
63 Answers
63
Active
...