Re: [Pytables-users] ValueError when a list of numarray.arrays used.

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

Hi Daehyok,

The ultimate reason for this is that numarray.records.array cannot convert a
list of arrays to a RecArray. See:

In [27]: records.array([[1.,2.]]*3, formats='f8,f8')
Out[27]:
array(
[(1.0, 2.0),
(1.0, 2.0),
(1.0, 2.0)],
formats=['1Float64', '1Float64'],
shape=3,
names=['c1', 'c2'])

That works well. But...

In [28]: records.array([array([1.,2.])]*3, formats='f8,f8')
---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)

/home/falted/python.nobackup/IM-2004.01.05/<console>

/usr/local/lib/python2.3/site-packages/numarray/records.py in array(buffer, formats, shape, names, byteorder, aligned)
    382         if isinstance(buffer[0], num.NumArray) or isinstance(buffer[0], chararray.CharArray):
    383             return fromarrays(buffer, formats=formats, shape=shape, names=names,
--> 384                         byteorder=byteorder, aligned=aligned)
    385         else:
    386             return fromrecords(buffer, formats=formats, shape=shape, names=names,

/usr/local/lib/python2.3/site-packages/numarray/records.py in fromarrays(arrayList, formats, names, shape, byteorder, aligned)
    183     for i in range(len(arrayList)):
    184         try:
--> 185             _array.field(_array._names[i])[:] = arrayList[i]
    186         except TypeError: # trap only TypeError to get better messages
    187             raise TypeError, "Incorrect format %s, copy unsuccessful." % _array._formats[i]

IndexError: list index out of range

does not work.

Perhaps, this worked with previous versions of numarray, I can't remember.
Anyway, I'll remove the part of manual where I say that Table.append() do
accept lists of numarrays/Numeric/chararray.

Cheers,

Francesc

A Divendres 08 Octubre 2004 23:17, Shin va escriure:
> While filling up a table, I met a strange error message.
> When the appended program is tried with version 0.8.1,
> only the second trial to use a list of arrays raises an ValueError.
> But, the manual says I can use a list of numarrays to append multi-rows.
> What did I miss? Or, a bug? Thanks.
> 
> >>>>>>>>>>>>>>> test3.py <<<<<<<<<<<<<<<<<<
> 
> #!/usr/bin/env python
> 
> from numarray import *
> from tables import *
> 
> # By using a list of lists.
> class Cols(IsDescription):
>     V1 = FloatCol()
>     V2 = FloatCol()    
> 
> f = openFile("test.hd5", "w")
> tab = f.createTable("/","Data",Cols,"Data")
> 
> d = []
> for i in range(10):
>     d = d + [[1.0,1.0]]
> 
> tab.append(d)
> f.close()
> 
> # By using a list of arrays.
> 
> f = openFile("test.hd5", "w")
> tab = f.createTable("/","Data",Cols,"Data")
> 
> d = []
> for i in range(10):
>     d = d + [array([1.0,1.0])]
> 
> tab.append(d)
> f.close()
> 
> >>>>>>>>> Here is the error message caught in ipython <<<<<<
> 
> In [1]: execfile("test3.py")
> ---------------------------------------------------------------------------
> ValueError                                Traceback (most recent call
> last)
> 
> /home/sdhyok/catchlab/catchlab/catchlab/pkg/rhessys/test/<console> 
> 
> /home/sdhyok/catchlab/catchlab/catchlab/pkg/rhessys/test/test3.py 
>      24 for i in range(10):
>      25     d = d + [array([1.0,1.0])]
>      26 
> ---> 27 tab.append(d)
>         tab = /Data (Table(0,)) 'Data'
>   description := {
>     ...pe=1, dflt=0.0, pos=None) }
>   byteorder := little, global append = undefined, d = [array([ 1., 
> 1.]), array([ 1.,  1.]), array([ 1.,  1.]), array([ 1.,  1.]), array([
> 1.,  1.]), array([ 1.,  1.]), array([ 1.,  1.]), array([ 1.,  1.]),
> array([ 1.,  1.]), array([ 1.,  1.])]
>      28 f.close()
> 
> /usr/lib/python2.3/site-packages/tables/Table.py in append(self=/Data
> (Table(0,)) 'Data'
>   description := {
>     ...pe=1, dflt=0.0, pos=None) }
>   byteorder := little, rows=[array([ 1.,  1.]), array([ 1.,  1.]),
> array([ 1.,  1.]), array([ 1.,  1.]), array([ 1.,  1.]), array([ 1., 
> 1.]), array([ 1.,  1.]), array([ 1.,  1.]), array([ 1.,  1.]), array([
> 1.,  1.])])
>     588         except:
>     589             (type, value, traceback) = sys.exc_info()
> --> 590             raise ValueError, \
>         global ValueError = undefined, global str = undefined, self =
> /Data (Table(0,)) 'Data'
>   description := {
>     ...pe=1, dflt=0.0, pos=None) }
>   byteorder := little, value = <exceptions.IndexError instance>
>     591 "rows parameter cannot be converted into a recarray object
> compliant with table '%s'. The error was: <%s>" % (str(self), value)
>     592         lenrows = recarray.shape[0]
> 
> ValueError: rows parameter cannot be converted into a recarray object
> compliant with table '/Data (Table(0,)) 'Data''. The error was: <list
> index out of range>
> 

-- 
Francesc Alted