[Numpy-discussion] Problem while writing array with np.savetxt

[Andrew Nelson]

Dear list,
whilst trying to write an array to disk I am coming across the following.
What am I doing wrong? Surely f is a file handle?
(python 3.4.3, numpy 1.9.2)

import numpy as np
a = np.arange(10.)
with open('test.dat', 'w') as f:
np.savetxt(f, a)

---------------------------------------------------------------------------

TypeError Traceback (most recent call
last)<ipython-input-57-cf77f423517e> in <module>() 2 a =
np.arange(10.) 3 with open('test.dat', 'w') as f:----> 4
np.savetxt(f, a)
/Users/anz/Documents/Andy/programming/dev3/lib/python3.4/site-packages/numpy/lib/npyio.py
in savetxt(fname, X, fmt, delimiter, newline, header, footer,
comments) 1085 else: 1086 for row in X:-> 1087
fh.write(asbytes(format % tuple(row) + newline))
1088 if len(footer) > 0: 1089 footer =
footer.replace('\n', '\n' + comments)
TypeError: must be str, not bytes

[Eric Firing]

Post by Andrew Nelson
Dear list,
whilst trying to write an array to disk I am coming across the
following. What am I doing wrong? Surely f is a file handle?
(python 3.4.3, numpy 1.9.2)
import numpy as np
a = np.arange(10.)
np.savetxt(f, a)

It will work if you open with 'wb'. Yes, this seems like a bug; or at
least, the anomaly should be noted in the docstring.

Eric

Post by Andrew Nelson
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
<ipython-input-57-cf77f423517e> in<module>() 2 a = np.arange(10.)3 with open('test.dat', 'w') as f:---->
4np.savetxt(f,
a)/Users/anz/Documents/Andy/programming/dev3/lib/python3.4/site-packages/numpy/lib/npyio.py
in savetxt(fname, X, fmt, delimiter, newline, header, footer, comments)
1085 else:1086 for row in X:-> 1087fh.write(asbytes(format % tuple(row)
+ newline))1088 if len(footer) > 0:1089 footer = footer.replace('\n',
'\n' + comments)TypeError: must be str, not bytes
--
_____________________________________
Dr. Andrew Nelson
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[Julian Taylor]

numpy text io is fundamentally broken in python3, there are sometimes
workarounds, but currently its probably best to stick to python2 or not
use it.
The workarounds usually just make actually fixing the functions harder.

Post by Eric Firing

Post by Andrew Nelson
Dear list,
whilst trying to write an array to disk I am coming across the
following. What am I doing wrong? Surely f is a file handle?
(python 3.4.3, numpy 1.9.2)
import numpy as np
a = np.arange(10.)
np.savetxt(f, a)

It will work if you open with 'wb'. Yes, this seems like a bug; or at
least, the anomaly should be noted in the docstring.
Eric

Post by Andrew Nelson
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
<ipython-input-57-cf77f423517e> in<module>() 2 a = np.arange(10.)3
with open('test.dat', 'w') as f:---->
4np.savetxt(f,
a)/Users/anz/Documents/Andy/programming/dev3/lib/python3.4/site-packages/numpy/lib/npyio.py
in savetxt(fname, X, fmt, delimiter, newline, header, footer, comments)
1085 else:1086 for row in X:-> 1087fh.write(asbytes(format % tuple(row)
+ newline))1088 if len(footer) > 0:1089 footer = footer.replace('\n',
'\n' + comments)TypeError: must be str, not bytes
--
_____________________________________
Dr. Andrew Nelson
_____________________________________
_______________________________________________
NumPy-Discussion mailing list
https://mail.scipy.org/mailman/listinfo/numpy-discussion

_______________________________________________
NumPy-Discussion mailing list
https://mail.scipy.org/mailman/listinfo/numpy-discussion