There is a bug report about fromstring. This bug report is correct. The docstring differs from the documentation, which only mentions the two-argument form (string, typecode). Numeric itself uses the latter form. The implementation has the 'count' argument but implemented incorrectly, without allowing for keyword arguments. In order to reconcile this with the least damage to the most people, I have changed the signature to: fromstring(string, typecode='l', count=-1) and allowed keyword arguments. This does not break the arguments as advertised in the documentation but does break any explicitly three-argument call in the old order. I will commit to CVS and this will be in 2.3 unless someone mean yells at me.