Hi All, I have been using Numpy for a while with great success. I left my little project for a little while (http://web.mit.edu/stardev/cluster/) and now some of my code is broken. I have some Numpy code to create graphs of activity on a cluster with matplotlib. It ran just fine in July / August 2010, but has since stopped working. I have updated numpy on my machine, I think. In [2]: np.version.version Out[2]: '1.5.1' My call to np.rec.fromrecords() is throwing this exception: File "/home/rajat/Envs/StarCluster/lib/python2.6/site-packages/numpy/core/records.py", line 607, in fromrecords descr = sb.dtype((record, dtype)) ValueError: invalid itemsize in generic type tuple Here is the code with some irrelevant stuff stripped: for line in file: a = [datetime.strptime(parts[0], '%Y-%m-%d %H:%M:%S.%f'), int(parts[1]), int(parts[2]), int(parts[3]), int(parts[4]), int(parts[5]), int(parts[6]), float(parts[7])] list.append(a) file.close() names = ['dt', 'hosts', 'running_jobs', 'queued_jobs',\ 'slots', 'avg_duration', 'avg_wait', 'avg_load'] descriptor = {'names': ('dt,hosts,running_jobs,queued_jobs,slots,avg_duration,avg_wait,avg_load'),\ 'formats' : ('S20','u','u','u','u','u','u','f')} self.records = np.rec.fromrecords(list,','.join(names)) #used to work #self.records = np.rec.fromrecords(list, dtype=descriptor) #new attempt Here is one "line" from the array "list":

...

...

parts (8) = ['2010-12-07 03:09:46.855712', '2', '2', '177', '2', '86', '370', '1.05'].

Neither of those np.rec.fromrecords() calls works. I've tried both separately. They both throw the exact same exception, ValueError: invalid itemsize in generic type tuple Can anybody help me? Am I doing something dumb? Thank you. Rajat Banerjee Masters Candidate, Computer Science, Harvard University