[R] subset a matrix

[Peter Ehlers]

Assuming that you want odd-numbered rows/cols, the
seq() function is handy, as in:

mat <- matrix(1:(20*30), nr = 20)
mat1 <- mat[seq(1, 19, by = 2), seq(1, 29, by = 2)]

Peter Ehlers

zhijie zhang wrote:

> Dear friends,
>  I have a (20*30) matrix,and want to get a subset of it like the following:
> The original matrix: rows:1,2,3,....20;     columns:1,2,3,....30
> I want to get my subset of The original matrix and delete others:
>    rows:1,3,5,7,...19;   columns:1,3,5.....29
> 
> 
> --
> Kind Regards,Zhi Jie,Zhang ,PHDDepartment of EpidemiologySchool of Public
> HealthFudan UniversityTel:86-21-54237149
> 
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