HELP !!How i can write .mat file to other .mat file ?

    mjp = 0;

   for jp = 1:1:10

       mjp = mjp +1;

   ndata_first(jp,1) = ndata_x_ab(mjp,1);
   ndata_first(jp,2) = ndata_x_ab(mjp,2);
   ndata_first(jp,3) = ndata_x_ab(mjp,3);

   end

error:

Index exceeds matrix dimensions.

Error in pointCloudDemo2 (line 3021) ndata_first(jp,1) = ndata_x_ab(mjp,1);

[Rik]

Apparently the matrix ndata_x_ab has less than 10 rows.

[KSSV]

Number of rows ndata_x_a should be more then 10. In your case it is not.