On Fri, 28 Jul 2006 12:17:39 -0500 "Tom Denniston" <[EMAIL PROTECTED]> wrote:
> It seems that object arrays will not pickle if they have a nan when > the pickle protocol is set to binary. From what I can tell the object > array simply delegates to python (which makes sense) which in turn > cannot pickle nans in binary format. It is unfortunate because it is > very useful to have heterogenous arrays that include nans. What do > other people do in this situation? Does anyone know why python has > this limitation? Is there an intelligent workaround other than search > and replace? Would it be worth it to put an intelligent workaround > into numpy so it is transparent to the user? I was wondering what > people thought. > > Code that reproduces the problem: > > This is regular python: > pickle.dumps(numpy.nan, 2) > SystemError: frexp() result out of range > > This is fine in numpy: > pickle.dumps(numpy.array([numpy.nan]), 2) > > This breaks: > pickle.dumps(numpy.array([numpy.nan], numpy.PyObject), 2) > SystemError: frexp() result out of range I believe this will be fixed in Python 2.5 (see http://www.python.org/sf/445484). I guess your best alternative would be to use a numpy scalar object (like double) instead of a Python float for NaN's. -- |>|\/|< /--------------------------------------------------------------------------\ |David M. Cooke http://arbutus.physics.mcmaster.ca/dmc/ |[EMAIL PROTECTED] ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys -- and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Numpy-discussion mailing list Numpy-discussion@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/numpy-discussion
