Re: [Pytables-users] empty strings and whitespace

[Francesc A. <fa...@ca...>]

Hi Stefan,

A Divendres 09 Desembre 2005 18:49, Stefan Kuzminski va escriure:
> If I run the following code..
>
> fp =3D openFile( 'tmp.h5', 'w' )
> desc =3D { 'a' : StringCol( length=3D8 ) }
> table =3D fp.createTable( fp.root, 'foobar', desc )
> table.append( [['spam'],['']] )
> table.flush()
> print table.read()
>
> it prints out
>
> NestedRecArray[
> ('spam'),
> (' ')
> ]
>
> Note that the second string in the append was a empty string, but what
> is read and printed is a single space, is there a reason for this or a
> way around it?

Yes, there is a reason for this, not exactly related with PyTables but
with the interaction of numarray and the FITS library.

You can read more about this issue in:

http://sourceforge.net/tracker/index.php?func=3Ddetail&aid=3D1304615&group_=
id=3D1369&atid=3D450446

A workaround is to patch the numarray sources in your local
installation:

=2D-- /usr/lib/python2.3/site-packages/numarray-1.5.0-py2.3-linux-i686.egg/=
numarray/records.py.orig=20
2005-12-09 19:22:46.870629670 +0100
+++ /usr/lib/python2.3/site-packages/numarray-1.5.0-py2.3-linux-i686.egg/nu=
marray/records.py     =20
2005-12-09 19:23:01.023381709 +0100
@@ -101,7 +101,7 @@
             arrlist[col] =3D num.array(tmp)
         except:
             try:
=2D                arrlist[col] =3D chararray.array(tmp)
+                arrlist[col] =3D chararray.array(tmp, padc=3D'\x00')
             except:
                 raise ValueError, "inconsistent data at row %d,field %d" %=
=20
(row, col)
     _array =3D fromarrays(arrlist, formats=3Dformats, shape=3D_shape, name=
s=3Dnames,

Perhaps if users start to request a more 'reasonable' behaviour for
the numarray.strings, we can lobby for a better solution in numarray.=20

Sorry about that,

=2D-=20
>0,0<   Francesc Altet =A0 =A0 http://www.carabos.com/
V   V   C=E1rabos Coop. V. =A0=A0Enjoy Data
 "-"