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<P><FONT SIZE=2 FACE="Arial">Hello,</FONT>
<BR><FONT SIZE=2 FACE="Arial"> We are having some problems adding arrays of scalars to an unstructured grid. We are doing the following:</FONT>
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<P><FONT SIZE=2 FACE="Arial">mygrid = <appendfilter>->GetOutput()</FONT>
<BR><FONT SIZE=2 FACE="Arial">vtkDoubleArray *data = vtkDoubleArray::New();</FONT>
<BR><FONT SIZE=2 FACE="Arial">(set num tuples, components, allocate, fill data, set name, etc)</FONT>
<BR><FONT SIZE=2 FACE="Arial">mygrid->GetCellData()->AddArray( data );</FONT>
<BR><FONT SIZE=2 FACE="Arial">data->Delete()</FONT>
<BR><FONT SIZE=2 FACE="Arial">...</FONT>
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<P><FONT SIZE=2 FACE="Arial">At this point, if we write the grid to an xml file, the file contains an array section with the correct name in the cell data section, but the data values themselves are missing. If we run the grid through a vtkExtractUnstructuredGrid filter before we write the xml file, then all the data is there as expected. We have verified that the array dimensions match the number of cells in the grid. We have tried with versions 4.2 and 4.4.2, and get the same results with both.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">The one clue I found in the archives was a statement that you can't change an object in the middle of a pipeline, and that something like a vtkMergeDataObjectFilter must be used. If that is the case, why does everything work correctly if I go though a filter before writing the grid? What am I missing? </FONT></P>
<P><FONT SIZE=2 FACE="Arial">Thank you,</FONT>
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<P><FONT FACE="Times New Roman">RAYMOND C. MAPLE, Lt Col USAF</FONT>
<BR><FONT FACE="Times New Roman">Deputy Head, Department of Aeronautics and Astronautics</FONT>
<BR><FONT FACE="Times New Roman">Air Force Institute of Technology</FONT>
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<P><FONT FACE="Times New Roman">RAYMOND C. MAPLE, Lt Col USAF</FONT>
<BR><FONT FACE="Times New Roman">Deputy Head, Department of Aeronautics and Astronautics</FONT>
<BR><FONT FACE="Times New Roman">Air Force Institute of Technology</FONT>
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