Thanks for the reply. On 11/17/10 7:00 PM, Pauli Virtanen<[email protected]> wrote: > > Wed, 17 Nov 2010 08:40:50 +0100, Laurent Gautier wrote: > [clip] >> > __main__:1: RuntimeWarning: Item size computed from the PEP 3118 buffer >> > format string does not match the actual item size. > [clip] >> > I tried tracing a bit further but I am a little confused by what is the >> > intent (a lot of nested calls). > Numpy is warning you that the view that you passed to it is inconsistent, > and it indicates that it refuses to consider it as a PEP 3118 buffer. If > you use it on Python 2.x, it probably falls back to using the legacy > buffer interface which does not care about the format string.
That would be the __array_struct__ attribute, I suppose. >> > my buffer format is 'f', and the view has itemsize set as: >> > view->itemsize = sizeof(double); >> > >> > Any pointer regarding what might be going on ? > Seehttp://docs.python.org/library/struct.html#format-strings > > The format 'f' means 32-bit float, so the view itemsize should be > sizeof(float) and not sizeof(double). If your view really contains floats > in sizeof(double) bytes, the buffer format string probably should > indicate the padding. It seems that I have been mislead by some documentation (which I cannot find again). I had something that 'f' indicated a "Python float", which I understand to be represented by a double at C-level. Laurent > -- Pauli Virtanen _______________________________________________ NumPy-Discussion mailing list [email protected] http://mail.scipy.org/mailman/listinfo/numpy-discussion
