[R] number of zeros in a matrix -row by row

[Dimitris Rizopoulos]

if 'M' is your matrix, then try this:

rowSums(M == 0)


I hope it helps.

Best,
Dimitris


onyourmark wrote:
> Hi. I have an n x m matrix M some of who's entries are zeros. I want to know
> how many zeros there are in each row    -perhaps stored in a 1 x n vector
> which lists the number of zeros for each row of M.
> 
> Before I had a vector V and I was able to get the number of zeros in V by
> doing length(V[ V==0]) but when I try something similar for M, like M[ M==0]
> it creates a vector not a matrix and so this does not work. Does anyone have
> a solution to this?
> 
> Thank you.

-- 
Dimitris Rizopoulos
Assistant Professor
Department of Biostatistics
Erasmus University Medical Center

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