Hi there, In therms of bug hunting I recently found out that the Icon View (in GRETL for Windows) is not refreshed properly when doing this <>hansl nulldata 50 bundle foo loop for i=1..240 -q if i=2*int(i/2) matrix even_M$i={} sprintf mn "%d", i string bn = "even_M" ~ mn foo[bn]=even_M$i delete even_M$i else matrix odd_M$i={} sprintf mn "%d", i string bn = "odd_M" ~ mn foo[bn]=odd_M$i delete odd_M$i endif endloop <>hansl The bunch of matrix objects seems to be still there although delete them but closing and reopening the icon view solves 'the problem'. Merry Christmas! Leon