[...] > If you think so :) Ususally people go for dictionaries in such cases. you are right, I didn't think about dictionaries >>> p = "complex(1-1e-%i, 1-1e-%i)" >>> d={} >>> [d.update({i:eval(p % (i,i))}) for i in range(20,30)] [None, None, None, None, None, None, None, None, None, None] so now the work is complete :) Regards