Robert and Stavros, I downloaded the new 'numericalio' as instructed. Reading my 3.12MB file with maxima.bat, a : readlist(), it took about 5 seconds. Reading my 3.12MB file with wxmaxima, a : readlist(), it still took almost 2 hours, it would display of course, wxmaxima was still active. first(a) responded fine. Thank you.