[Gretl-users] two answers

Dear all, I have two quick problems: 1) I have a database which have monthly data. I want to compact the data restricting the original database. In doing so, I have made the following loop: loop i=2002..2012 --progressive loop j=1..12 --progressive smpl Destino=1 && Familia=2 && Anio=i && Mes=j --restrict M[132+(i-2002)*12+j,2]=nobs(Anio) smpl full endloop endloop which store each sample in a matrix. The problem is that sometimes the result from the restriction is null. In that case, the loop breaks and stop running. I know that I have to use the if command, but I do not how. What I want to do is that if the result of the restriction is null, then to store a N/A, and continue the loop. 2) The second point I want to know is if there is a chance to put "labels", strings should be the right word, in the first row of the matrix. Thanks, Leandro