[Paraview] reducing load time?

[John Doe]

I have a vector of N points.  So the number of doubles in 3*N.  A
double is 8 long.  Base 64 produces 4/3 the number of original bytes.

As expected my base64 string is 3*N*8 * (4/3)

So for 1417 points, I should expect a string 45344 characters long.

Paraview claims my string is too short:
ERROR: In /home/jsanchez/ParaView3/VTK/IO/vtkXMLUnstructuredDataReader.cxx,
line 522
vtkXMLUnstructuredGridReader (0x4dde7e0): Cannot read points array
from Points in piece 0.  The data array in the element may be too
short.

Here is the header I am writing:
<UnstructuredGrid>
<Piece NumberOfPoints="1417" NumberOfCells="8781">
<Points>
<DataArray type="Float64" NumberOfComponents="3" format="binary">
this is where my raw base64 encoding string goes
</DataArray>
</Points>

What could be wrong with my string of characters?

Thanks,

Juan


On Wed, Oct 15, 2008 at 6:05 PM, Berk Geveci <berk.geveci at kitware.com> wrote:
> By the way, if you are willing to link against the VTK libraries, VTK
> has a C/Fortran interface to write XML files.
>
> -berk
>
> On Wed, Oct 15, 2008 at 4:48 PM, John Doe <ufnoise at gmail.com> wrote:
>> Hello,
>>
>> Thanks for the suggestion.  I assume that for double precision I am
>> doing a base64 encoding for every number in the list?  Is compression
>> worthwhile for floating point data?  Are there free compression
>> libraries out there?
>>
>> Juan
>>
>> On Wed, Oct 15, 2008 at 3:26 PM, Berk Geveci <berk.geveci at kitware.com> wrote:
>>> ASCII XML is very slow to load because it uses the XML parser. For
>>> large data, you should switch to a binary format.
>>>
>>> XML binary
>>> legacy VTK
>>> Exodus
>>> Xdmf
>>>
>>> are a few choices.
>>>
>>> To see the difference in load time, save the data out as a binary vtu
>>> or vtk file and load it back in.
>>>
>>> -berk
>>>
>>> On Wed, Oct 15, 2008 at 3:25 PM, John Doe <ufnoise at gmail.com> wrote:
>>>> Hi,
>>>>
>>>> I have a 220 MB vtu file that is being loaded and it is taking at
>>>> least 15 min to load the data.  Is there any option to reduce the
>>>> amount of time paraview would take to load the data.  Or is there some
>>>> way I should be formatting my data.  The vtu file is in the ASCII XML
>>>> VTK format.
>>>>
>>>> Thanks,
>>>>
>>>> Juan
>>>> _______________________________________________
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>>>> ParaView at paraview.org
>>>> http://www.paraview.org/mailman/listinfo/paraview
>>>>
>>>
>>
>