R help - Feb 2009 - replace zeros in a block diagonal matrix with small random values?

Hi All.

Imagine you have a large block diagonal matrix.  I'd like to replace
the zeros in this matrix with small random (runif) numbers.  Any ideas
for a simple and efficient way to do this?

Best regards,

Rick DeShon

say 'mat' is your matrix, then you could try something like (untested):

ind <- mat == 0
mat[ind] <- runif(sum(ind))


I hope it helps.

Best,
Dimitris

Rick DeShon wrote:
> Hi All.
> 
> Imagine you have a large block diagonal matrix.  I'd like to replace
> the zeros in this matrix with small random (runif) numbers.  Any ideas
> for a simple and efficient way to do this?
> 
> Best regards,
> 
> Rick DeShon
> 
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-- 
Dimitris Rizopoulos
Assistant Professor
Department of Biostatistics
Erasmus University Medical Center

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