Hi Allin and all, As I was trying to find a way to create an empty matrix with all NaN’s, it didn’t work. So I tried the command "matrix m = zeros(2,2) * .NaN” on the gretl console, and gretl crashed. This is a repeatable crash. On the gretl console, after I have created a matrix m, if I type, for example, m[1,1]=.NaN, gretl will crash. So, my question is also how to create a matrix of NaN’s? BTW, I’m using MacBook pro on Mac OS X 10.14.6. My version of gretl is 2020c-git, build data 2020-5-4 Thanks in advance. Fred Attached is the crash report.