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numpy.fromfile OSError: first argument must be an open file (Python 3)

See original GitHub issue

Using Python 3 and Numpy 1.9.2 there is an issue with numpy.fromfile when called on an existing file object. This code works fine in Python 2.7.

$ fh
<_io.FileIO name=8 mode='rb+'>
$ np.fromfile(fh, dtype=dtype, count=length)
OSError: first argument must be an open file

I’ve checked fh.closed is False, so the file is still open. The error is thrown by numpy.multiarraymodule.c#2119.

Someone mentioned these issues on Stack Overflow, but no clear solutions are present.

Any suggestions?

Issue Analytics

State:
Created 8 years ago
Comments:12 (9 by maintainers)

Top GitHub Comments

1reaction

rpratt20commented, Oct 8, 2015

Someone pointed out to me that fromfile is designed to read straight from a file and not buffered. Using this: trace.data = np.frombuffer(fpin.read(record_dtype.itemsize * npts), record_dtype) gives me correct input so there probably is no issue. Thanks.

Randy ----- Original Message ----- From: W. Trevor King To: numpy/numpy Cc: rpratt20 Sent: Wednesday, October 07, 2015 2:35 PM Subject: Re: [numpy] numpy.fromfile OSError: first argument must be an open file (Python 3) (#6246)

Is this closable now that #6330 has landed, or should it stay open until @rpratt20’s Python 2 issue has been addressed?

— Reply to this email directly or view it on GitHub.

0reactions

cjermaincommented, Oct 8, 2015

Thanks @charris!