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How to Correctly Use Lists in R?
...Why do these two expressions not return the same result?
x = list(1, 2, 3, 4); x2 = list(1:4)
A list can contain any other class as each element. So you can have a list where the first element is a character vector, the second is a data frame, etc. In this case, you have created two different lis...
PHP: merge two arrays while keeping keys instead of reindexing?
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564
You can simply 'add' the arrays:
>> $a = array(1, 2, 3);
array (
0 => 1,
1 => 2...
Why does parseInt yield NaN with Array#map?
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483
The callback function in Array.map has three parameters:
From the same Mozilla page that you ...
How can I profile Python code line-by-line?
...s intended for. From the link:
File: pystone.py
Function: Proc2 at line 149
Total time: 0.606656 s
Line # Hits Time Per Hit % Time Line Contents
==============================================================
149 @profile
150 ...
How assignment works with Python list slice?
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4 Answers
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Split delimited strings in a column and insert as new rows [duplicate]
... of doing it..
df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F)
df
## V1 V2
## 1 1 a,b,c
## 2 2 a,c
## 3 3 b,d
## 4 4 e,f
s <- strsplit(df$V2, split = ",")
data.frame(V1 = rep(df$V1, sapply(s, length)), V2 = unlist(...
Map Tiling Algorithm
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edited Jan 22 '13 at 8:54
answered Jan 22 '13 at 8:44
use...
Bomb dropping algorithm
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edited Mar 9 '13 at 8:46
community wiki
4 r...
How to randomly sort (scramble) an array in Ruby?
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Built in now:
[1,2,3,4].shuffle => [2, 1, 3, 4]
[1,2,3,4].shuffle => [1, 3, 2, 4]
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f...
What is the most efficient way to create a dictionary of two pandas Dataframe columns?
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4 Answers
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