On Thu, 15 Oct 2015, Artur T. wrote: Yes, it's intended. There's really no such thing as NA in a gretl matrix, the "closest translation" is NaN (not-a-number) and that's what gets written into the matrix if you give NA as an element. And NaN (a standard C-library/IEEE concept) turns everything it touches into another NaN: x + NaN = NaN, x * NaN = NaN, and so on. How are NAs (NaNs) getting into your matrix? Why do you think they ought to be ignored/skipped instead of propagating when doing calculations on the matrix? Allin Cottrell

Thank you for the quick answers. Now I remember that there was a related discussion on the list a while ago. I understand the issues related to NAs in matrices, and actually it is not a big problem at all as there are ways to circumvent this easily. to be ignored/skipped instead of propagating when doing calculations on the matrix? I simply that I run a loop filling some columns of a zero matrix, but the length of the resulting column vectors vary. Hence, some entries remain zero, but before computing meanc(), I would like to discard the zero entries. However, Jack's solution is just doing its job. Thank you, Jack! Best wishes, Artur 2015-10-15 2:02 GMT+02:00 Allin Cottrell <cottrell(a)wfu.edu&gt;: > On Thu, 15 Oct 2015, Artur T. wrote: > > Dear all, >> >> I would like to compute the mean of a vector which involves NAs, implying >> that the NAs should simply be neglected/not counted. But this is not the >> way gretl handles matrices: >> >> <gretl> >> matrix A = {NA, 1; 2, 2; 1, 3} >> mA = meanc(A) >> mA >> </gretl> >> >> yields >> >> <output> >> mA (1 x 2) >> nan 2 >> </output> >> >> Is this intended? For instance, R, it seems, fully neglects the NAs and >> computes the mean. >> > > Yes, it's intended. There's really no such thing as NA in a gretl matrix, > the "closest translation" is NaN (not-a-number) and that's what gets > written into the matrix if you give NA as an element. And NaN (a standard > C-library/IEEE concept) turns everything it touches into another NaN: x + > NaN = NaN, x * NaN = NaN, and so on. > > to be ignored/skipped instead of propagating when doing calculations on the > matrix? > > Allin Cottrell > > _______________________________________________ > Gretl-users mailing list > Gretl-users(a)lists.wfu.edu > http://lists.wfu.edu/mailman/listinfo/gretl-users >