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What's the algorithm to calculate aspect ratio?
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Principal component analysis in Python
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In Typescript, How to check if a string is Numeric
...y to convert a string to a number is with Number, not parseFloat.
Number('1234') // 1234
Number('9BX9') // NaN
You can also use the unary plus operator if you like shorthand:
+'1234' // 1234
+'9BX9' // NaN
Be careful when checking against NaN (the operator === and !== don't work as expected wi...
How to run cron job every 2 hours
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edited Jul 14 '18 at 14:09
Mark Amery
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Add subdomain to localhost URL
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Unfortunately, because localhost is not a proper domain, you can't add a subdomain to it like ...
Seeding the random number generator in Javascript
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How to get the seconds since epoch from the time + date output of gmtime()?
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If you got here because a search engine told you this is how to get the Unix timestamp, stop r...
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=...