[R] removing for loop

[Uwe Ligges]

vincent at 7d4.com wrote:
> Dear Rusers,
> 
> Trying to reduce my for loops addiction,
> could somebody tell me if there are ways to simplify
> (and perhaps accelerate ?) the following line
> 
> for (i in 1:N) for (j in 1:N) m[i,j] = b[i]-b[j];


outer(b, b, "-")

Uwe Ligges


> (where m is a NxN matrix and b a vector of length N)
> 
> Thanks for any hint.
> 
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