On Sep 18, 2011, at 11:55 AM, Alex van der Spek wrote: > Why does this not work? > >>>> dat=[[1,2,3],[4,5,6]] >>>> col=[('a','f4'),('b','f4'),('c','f4')] >>>> arr=numpy.array(dat,dtype=col) > > Traceback (most recent call last): > File "<pyshell#91>", line 1, in <module> > arr=numpy.array(dat,dtype=col) > TypeError: expected a readable buffer object > > But this does: > >>>> dat=[(1,2,3),(4,5,6)] >>>> arr=numpy.array(dat,dtype=col) >>>> arr > array([(1.0, 2.0, 3.0), (4.0, 5.0, 6.0)], dtype=[('a', '<f4'), ('b', > '<f4'), ('c', '<f4')]) > > The only difference that the object is a list of tuples now?
I don't know why you're seeing what you're seeing, but if you don't get answer here you could try asking on the numpy list. Good luck Philip -- http://mail.python.org/mailman/listinfo/python-list