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LINQ where vs takewhile
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159
TakeWhile stops when the condition is false, Where continues and find all elements matching th...
With bash, how can I pipe standard error into another process?
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172
There is also process substitution. Which makes a process substitute for a file.
You can send...
What are the aspect ratios for all Android phone and tablet devices?
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162
In case anyone wanted more of a visual reference:
Decimal approximations reference table:
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How to check whether a pandas DataFrame is empty?
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edited Dec 15 '17 at 17:37
Dave Thomas
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How to form tuple column from two columns in Pandas
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edited Nov 7 '16 at 16:58
answered Apr 17 '13 at 19:24
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Does the ternary operator exist in R?
... returns the latest evaluation, if-else is equivalent to ?:.
> a <- 1
> x <- if(a==1) 1 else 2
> x
[1] 1
> x <- if(a==2) 1 else 2
> x
[1] 2
The power of R is vectorization. The vectorization of the ternary operator is ifelse:
> a <- c(1, 2, 1)
> x <- ifelse(a=...
Clojure: cons (seq) vs. conj (list)
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150
One difference is that conj accepts any number of arguments to insert into a collection, while...
Get operating system info
...that, it sniffs your core operating system model, for example windows nt 5.1 as my own.
It then passes windows nt 5.1/i to Windows XP as the operating system.
Using: '/windows nt 5.1/i' => 'Windows XP', from an array.
You could say guesswork, or an approximation yet nonetheless pretty much ba...
Select multiple columns in data.table by their numeric indices
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185
For versions of data.table >= 1.9.8, the following all just work:
library(data.table)
dt &...
How to split a string in shell and get the last field
Suppose I have the string 1:2:3:4:5 and I want to get its last field ( 5 in this case). How do I do that using Bash? I tried cut , but I don't know how to specify the last field with -f .
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