Re: [Pytables-users] Column gets updated but table does not reflect

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

On 4/30/12 12:08 PM, Alvaro Tejero Cantero wrote:
> Hi all,
>
> I created a table:
>
>>>> joins.createTable('/','spikes',{'t20k':pt.Int32Col(),'tetrode':pt.UInt8Col(), 'unit':pt.UInt8Col()},'Spike times')
> I populated it
>
>>>> joins.root.spikes.append(zip(np.arange(100),np.zeros(100), 3*np.ones(100)))
> now if I do
>
>>>> joins.root.spikes.cols.tetrode[:] = np.ones(100)
> I can see the updated value (all ones instead of zeros)
>
> If I fetch all the table in memory,
>
>>>> joins.root.spikes[:]
> I still see only the original zeros, i.e. the column update has not propagated

Hmm, I cannot reproduce this:

In [18]: joins = pt.openFile("joins.h5", "w")

In [19]: 
joins.createTable('/','spikes',{'t20k':pt.Int32Col(),'tetrode':pt.UInt8Col(), 
'unit':pt.UInt8Col()},'Spike times')
Out[19]:
/spikes (Table(0,)) 'Spike times'
   description := {
   "t20k": Int32Col(shape=(), dflt=0, pos=0),
   "tetrode": UInt8Col(shape=(), dflt=0, pos=1),
   "unit": UInt8Col(shape=(), dflt=0, pos=2)}
   byteorder := 'little'
   chunkshape := (10922,)

In [20]: joins.root.spikes.append(zip(np.arange(10),np.zeros(10), 
3*np.ones(10)))

In [22]: joins.root.spikes[:]
Out[22]:
array([(0, 0, 3), (1, 0, 3), (2, 0, 3), (3, 0, 3), (4, 0, 3), (5, 0, 3),
        (6, 0, 3), (7, 0, 3), (8, 0, 3), (9, 0, 3)],
       dtype=[('t20k', '<i4'), ('tetrode', 'u1'), ('unit', 'u1')])

In [23]: joins.root.spikes.cols.tetrode[:] = np.ones(10)

In [24]: joins.root.spikes[:]
Out[24]:
array([(0, 1, 3), (1, 1, 3), (2, 1, 3), (3, 1, 3), (4, 1, 3), (5, 1, 3),
        (6, 1, 3), (7, 1, 3), (8, 1, 3), (9, 1, 3)],
       dtype=[('t20k', '<i4'), ('tetrode', 'u1'), ('unit', 'u1')])

Which versions are you using?

-- 
Francesc Alted