<p>Hello,</p><p>I posted this on the ParaView list two weeks ago and
received no response, and I suspect it to be an error in the way VTK
parses ASCII floating point values. I assume that there is a simple fix.
I apologize if I should not be cross posting:</p>
<p>I'm not sure whether I should be emailing the ParaView or VTK lists
(or maybe both?), as the problem crashes ParaView but the error is
thrown from line 348 of VTK/IO/vtkXMLStructuredDataReader.cxx,</p>
<div><br></div>
<div>
<div> vtkErrorMacro("Error reading extent "</div>
<div> << this->SubExtent[0] << " " << this->SubExtent[1] << " "</div>
<div>
<< this->SubExtent[2] << " " << this->SubExtent[3] << " "</div>
<div> << this->SubExtent[4] << " " << this->SubExtent[5]</div>
<div> << " from piece " << this->Piece);</div>
</div>
<div><br></div>
<div>After some extensive tests, I have noticed that the error only
occurs when the floating point data in an ASCII ImageData file has
entries with exponents less than or equal to -309 (I am using Float64 as
the datatype). In case it helps, the meta data for the file is</div>
<div><br></div>
<div>
<div><?xml version="1.0"?></div>
<div><VTKFile type="ImageData" version="0.1"></div>
<div> <ImageData WholeExtent="0 40 0 40 0 1" Origin="0 0 0.487805" Spacing="0.0243902 0.0243902 0.0243902"></div>
<div> <Piece Extent="0 40 0 40 0 1"></div>
<div> <CellData Scalars="cell_scalars"></div>
<div> <DataArray type="Float64" Name="cell_scalars" format="ascii"></div>
</div>
<div>...</div>
<div>
<div> </DataArray></div>
<div> </CellData></div>
<div> </Piece></div>
<div> </ImageData></div>
<div></VTKFile></div>
</div>
<div><br></div>
<div>The DataArray contained 40 lines of 40 floating point values, and I
was experimenting with changing the exponent on the first entry. For
exponents equal to -308 or greater, the file opens without an error.
When I change it to -309 or less, an error is thrown when clicking
"Apply" and ParaView quickly crashes (thus I haven't been able to easily
write down the full error...).</div>
<div><br></div>
<div>I dug into the VTK code for a few minutes but was not able to
locate the exact source of the problem. Perhaps there is an overflow in
the ASCII parsing due to an assumption of a smaller exponent?<br><br>
I can easily avoid this problem by thresholding my output to zero when
it is sufficiently small, but I though I would report the problem
anyway.</div>
<div><br></div>
Best Regards,<br>Jack Poulson<br><div class="yj6qo ajU"><div id=":15n" class="ajR" tabindex="0"><img class="ajT" src="images/cleardot.gif"></div></div>