[Paraview] vtkDoubleArray with >3 components

Wed Jul 22 11:09:33 EDT 2015

The solution is in the documentation:

  // This method lets the user specify data to be held by the array.  The
  // array argument is a pointer to the data.  size is the size of the
  // array supplied by the user.  Set save to 1 to keep the class from
  // deleting the array when it cleans up or reallocates memory.  The class
  // uses the actual array provided; it does not copy the data from the
  // suppled array. If specified, the delete method determines how the data
  // array will be deallocated. If the delete method is
  // VTK_DATA_ARRAY_FREE, free() will be used. If the delete method is
  // DELETE, delete[] will be used. The default is FREE.

You are passing 0 for the "save" argument, which means that VTK will delete
the array when the VTK array object is deleted, which would cause a double
delete/free. Use 1 as the second argument of SetArray() if you are managing
the memory. Also, make sure that the VTK array is not used after you free
your array.

Best,
-berk

On Wed, Jul 22, 2015 at 9:56 AM, Bruce Jones <bruce.david.jones at gmail.com>
wrote:

> Hi Guys,
>
> I have just tried it as you suggested, doing SetNumberOfComponents then
> SetArray, without doing SetNumberOfTuples. Unfortunately I am still getting
> the same behaviour.
>
> Cheers,
> Bruce
>
> On Wed, 22 Jul 2015 at 09:44 Berk Geveci <berk.geveci at kitware.com> wrote:
>
>> Actually, don't call SetNumberOfTuples() at all if you are using
>> SetArray(). It will unnecessarily allocate memory if you call it before
>> SetArray().
>>
>> -berk
>>
>> On Wed, Jul 22, 2015 at 9:40 AM, Shawn Waldon <shawn.waldon at kitware.com>
>> wrote:
>>
>>> Hi Bruce,
>>>
>>> SetNumberOfTuples reallocates the internal datastructure of the data
>>> array to be the new required size based on the new number of components and
>>> number of tuples.  This (combined with trying to clean up the old data from
>>> SetArray) may be causing the heap corruption you are seeing.  Try setting
>>> the number of components and number of tuples before adding the data to the
>>> array.
>>>
>>> HTH,
>>> Shawn
>>>
>>> On Tue, Jul 21, 2015 at 1:37 PM, Bruce Jones <
>>> bruce.david.jones at gmail.com> wrote:
>>>
>>>> Hi Cory,
>>>>
>>>> Sorry for the delayed response, I've hit another more serious bug which
>>>> has been diverting my attention from this.
>>>>
>>>> Thanks for the state file, I haven't got it to work as I don't have
>>>> numpy set up, but I have also got this working with 9 component arrays in
>>>> paraview using a python script. However, I am now trying to port my python
>>>> plugin to c++ which is where I am seeing the error.
>>>>
>>>> In my plugin I want to output a vtkarray for each vtkarray in the input
>>>> dataset. The values in the output vtkarrays are interpolated from those in
>>>> the input vtkarrays. Rather than working directly on vtkarray objects, I am
>>>> allocating c++ arrays for each vtkarray, performing the interpolation, then
>>>> creating vtkDoubleArrays and using SetArray to pass a pointer to my
>>>> allocated c++ arrays to the output vtkarrays. The code for setting up the
>>>> output vtkarrays is roughly as follows
>>>>
>>>>                 vtkPointData *pointData = input->GetPointData();
>>>>                 vtkDataArray *dArray = pointData->GetArray(i);
>>>> vtkDoubleArray *vtkDArrayAve = vtkDoubleArray::New();
>>>> vtkDArrayAve->SetName(dArray->GetName());
>>>> vtkDArrayAve->SetArray(dArraysAve[i],hgrid->GetTotalCells(),0);
>>>> vtkDArrayAve->SetNumberOfComponents(numComponents[i]);
>>>> vtkDArrayAve->SetNumberOfTuples(hgrid->GetTotalCells());
>>>> output->GetPointData()->AddArray(vtkDArrayAve);
>>>>
>>>> dArraysAve is an array of pointers pointing to my c++ arrays
>>>> hgrid->GetTotalCells() returns the number of data points for my output
>>>>
>>>> I also have another mode of operation for this plugin, where I perform
>>>> the interpolation differently, in that function, if I make the call to
>>>> SetNumberOfComponents() some heap corruption occurs and I get a segfault
>>>> when I try to subsequently free my c++ arrays. Commenting out the call to
>>>> SetNumberOfComponents avoids the segfault, but then I am limited to single
>>>> component arrays. This is the more serious bug I mentioned, initially I
>>>> figured they were unrelated, but I can't deny the number of components
>>>> coincidence.
>>>>
>>>> Cheers,
>>>> Bruce
>>>>
>>>> On Thu, 16 Jul 2015 at 14:41 Cory Quammen <cory.quammen at kitware.com>
>>>> wrote:
>>>>
>>>>> Hi Bruce,
>>>>>
>>>>> I have attached a ParaView state file with a Programmable Source that
>>>>> produces a vtkPolyData with 100 random points and a point data array with 9
>>>>> components. It seems to display the various component ranges just fine.
>>>>>
>>>>> Best,
>>>>> Cory
>>>>>
>>>>> On Thu, Jul 16, 2015 at 11:14 AM, Cory Quammen <
>>>>> cory.quammen at kitware.com> wrote:
>>>>>
>>>>>> Hi Bruce,
>>>>>>
>>>>>> I haven't seen this, but ParaView may be interpreting this array as a
>>>>>> tensor field. Do you have a smallish test data file that you can share that
>>>>>> shows the problem?
>>>>>>
>>>>>> Thanks,
>>>>>> Cory
>>>>>>
>>>>>> On Sat, Jul 11, 2015 at 11:14 AM, Bruce Jones <
>>>>>> bruce.david.jones at gmail.com> wrote:
>>>>>>
>>>>>>> I am creating vtkDoubleArrays based on averaging some input data to
>>>>>>> a reduced set of points. The input data includes various vtk arrays which
>>>>>>> have 1, 3 and 9 components.
>>>>>>>
>>>>>>> After averaging, I am writing the data to c++ arrays, and creating a
>>>>>>> new vtkDoubleArray using the SetArray() function to pass the c++ arrays.
>>>>>>> This works fine for 1 and 3 component arrays, however for the 9 component
>>>>>>> arrays paraview shows that every element is set to 0.
>>>>>>>
>>>>>>> If I hardcode it so that 9 component arrays become 3 component
>>>>>>> arrays (reading only the first 3 components from the input array), then I
>>>>>>> get the correct data for the first 3 components, though I obviously need
>>>>>>> the other 6 components in the end.
>>>>>>>
>>>>>>> Has anyone encountered this before?
>>>>>>>
>>>>>>> Cheers,
>>>>>>> Bruce
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> Powered by www.kitware.com
>>>>>>>
>>>>>>> Visit other Kitware open-source projects at
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>>>>>>>
>>>>>>> Please keep messages on-topic and check the ParaView Wiki at:
>>>>>>> http://paraview.org/Wiki/ParaView
>>>>>>>
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>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Cory Quammen
>>>>>> R&D Engineer
>>>>>> Kitware, Inc.
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Cory Quammen
>>>>> R&D Engineer
>>>>> Kitware, Inc.
>>>>>
>>>>
>>>> _______________________________________________
>>>> Powered by www.kitware.com
>>>>
>>>> Visit other Kitware open-source projects at
>>>> http://www.kitware.com/opensource/opensource.html
>>>>
>>>> Please keep messages on-topic and check the ParaView Wiki at:
>>>> http://paraview.org/Wiki/ParaView
>>>>
>>>> Search the list archives at: http://markmail.org/search/?q=ParaView
>>>>
>>>> Follow this link to subscribe/unsubscribe:
>>>> http://public.kitware.com/mailman/listinfo/paraview
>>>>
>>>>
>>>
>>> _______________________________________________
>>> Powered by www.kitware.com
>>>
>>> Visit other Kitware open-source projects at
>>> http://www.kitware.com/opensource/opensource.html
>>>
>>> Please keep messages on-topic and check the ParaView Wiki at:
>>> http://paraview.org/Wiki/ParaView
>>>
>>> Search the list archives at: http://markmail.org/search/?q=ParaView
>>>
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>>
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