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    <blockquote type="cite">1. What the numbers 0 4 8 12 (line 24)
      represent?</blockquote>
    This is the offset array used by VTK for random access into data on
    the quadrature points data. To generate it you go cell by cell and
    accumulate the number of quadrature points used by each cell. The
    next cell's data offset is the sum of the previous cell's number of
    quadrature points.<br>
    <br>
    note that the documentation says that each array has a quadrature
    scheme dictionary, but this changed. the dictionaries are stored in
    the offeset array. we did this so that you only need to define one
    quadrature scheme dictionary for many arrays.<br>
    <br>
    <blockquote type="cite">2. What the QuadratureWeights are all zero
      (line 37)?</blockquote>
    Those aren't currently used in VTK but we have a place holder for
    them in case they are needed in user developed custom filters or
    later in VTK.<br>
    <br>
    <blockquote type="cite">3. In your example there are 4 cells with 4
      Gauss points in each cell. In total 16 Gauss points. If I want to
      assign to each Gauss point one value of stress or strain how I
      have to write those 16 values in xml format.</blockquote>
    in my example you would read this file into PV and apply&nbsp;
    "interpolate to quadrature points" and then "generate quadrature
    points".<br>
    <br>
    You're asking about writing the data on the Gauss points into the
    file. You have to store them in VTK FieldData and add an information
    key to each array that names the offset array. You have to order
    them correctly according to the offsets array and quadrature scheme.
    for example the pdf I sent before shows how each cell's quadrature
    points are ordered for one scheme. you won't write the points
    themselves, just the data values.<br>
    <br>
    the T FieldData array in the following file is an example of
    containing scalar values at quadrature points (watch out there's
    also a PointData array named T that stores the nodal values),
<a class="moz-txt-link-freetext" href="http://www.hpcvis.com/vis/images/vtk-quadrature-points-example/quadrature-points-example-2.vtu">http://www.hpcvis.com/vis/images/vtk-quadrature-points-example/quadrature-points-example-2.vtu</a><br>
    <br>
    after reading such a file into PV, you could see the arrays in the
    spreadsheet view but to see them in the 2d/3d view you'll need to
    apply the "generate quadrature points" filter to produce the point
    set and transfer the data onto it.<br>
    <br>
    <div class="moz-cite-prefix">On 12/01/2013 10:26 PM, Marios Mavros
      wrote:<br>
    </div>
    <blockquote
cite="mid:CA+0nUO_TBufE_PosTAwg4uhrSmAWSYCCC+fV5kwPB4toEK6rww@mail.gmail.com"
      type="cite">
      <div dir="ltr">Hi Burlen,
        <div><br>
        </div>
        <div>Your example was really helpful to understand many thing
          about the xml format and I want to thank you about that, but I
          still have some questions.</div>
        <div><br>
        </div>
        <div>1. What the numbers 0 4 8 12 (line 24) represent?</div>
        <div>2. What the QuadratureWeights are all zero (line 37)?</div>
        <div>3. In your example there are 4 cells with 4 Gauss points in
          each cell. In total 16 Gauss points. If I want to assign to
          each Gauss point one value of stress or strain how I have to
          write those 16 values in xml format. Can you please sent me an
          example with this information?</div>
        <div><br>
        </div>
        <div>Thank you very much&nbsp;</div>
        <div><br>
        </div>
        <div>Marios</div>
      </div>
      <div class="gmail_extra"><br>
        <br>
        <div class="gmail_quote">On Sat, Nov 30, 2013 at 4:28 PM, Burlen
          Loring <span dir="ltr">&lt;<a moz-do-not-send="true"
              href="mailto:bloring@lbl.gov" target="_blank">bloring@lbl.gov</a>&gt;</span>
          wrote:<br>
          <blockquote class="gmail_quote" style="margin:0 0 0
            .8ex;border-left:1px #ccc solid;padding-left:1ex">
            <div bgcolor="#FFFFFF" text="#000000">
              <div>Hi Mario,<br>
                <br>
                sending again to the list. the weights have 2 dimensions
                i (node id) and j (Gauss point id), so to generate
                ShapeFunctionWeights for a new
                QuadratureSchemeDefinition&nbsp; what you do is evaluate each
                shape function at each Gauss point. For the linear
                quadrilateral you'll end up with 16 weights. For example
                see the example<br>
                <br>
                <a moz-do-not-send="true"
href="http://www.hpcvis.com/vis/images/vtk-quadrature-points-example/vtk-quadrature-points-example.pdf"
                  target="_blank">http://www.hpcvis.com/vis/images/vtk-quadrature-points-example/vtk-quadrature-points-example.pdf</a><br>
                <a moz-do-not-send="true"
href="http://www.hpcvis.com/vis/images/vtk-quadrature-points-example/quadrature-points-example.vtu"
                  target="_blank">http://www.hpcvis.com/vis/images/vtk-quadrature-points-example/quadrature-points-example.vtu</a><span
                  class="HOEnZb"><font color="#888888"><br>
                    <br>
                    Burlen</font></span>
                <div>
                  <div class="h5"><br>
                    &nbsp;<br>
                    On 11/29/2013 3:34 PM, Marios Mavros wrote:<br>
                  </div>
                </div>
              </div>
              <div>
                <div class="h5">
                  <blockquote type="cite">
                    <div dir="ltr">Hi Burlen,
                      <div><br>
                      </div>
                      <div>I want to thank you for the information that
                        you send me. I read the paper and I try to made
                        a simple example in xml format for a 4 node
                        quadrilateral element but it didn't work for me.
                        Attached you will find the element formulation
                        that I used with the shape functions and a .vtu
                        file with my example. If I want to give 4 stress
                        values in the 4 Gauss points ( lets say 0.1 0.2
                        0.4 -0.1) can you please write in the .vtu file
                        the missing information in order to understand
                        haw I have to write a correct file in xml
                        format.</div>
                      <div><br>
                      </div>
                      <div>Thank you very much</div>
                      <div><br>
                      </div>
                      <div>Marios Mavros</div>
                    </div>
                    <div class="gmail_extra"><br>
                      <br>
                      <div class="gmail_quote">On Wed, Nov 27, 2013 at
                        2:56 PM, Burlen Loring <span dir="ltr">&lt;<a
                            moz-do-not-send="true"
                            href="mailto:bloring@lbl.gov"
                            target="_blank">bloring@lbl.gov</a>&gt;</span>
                        wrote:<br>
                        <blockquote class="gmail_quote" style="margin:0
                          0 0 .8ex;border-left:1px #ccc
                          solid;padding-left:1ex">
                          <div text="#000000" bgcolor="#FFFFFF"> You'll
                            need to use an XML file format. There's some
                            documentation in the following link. It's
                            slightly dated but should get you started. <a
                              moz-do-not-send="true"
href="http://www.vtk.org/Wiki/images/7/78/VTK-Quadrature-Point-Design-Doc.pdf"
                              target="_blank">http://www.vtk.org/Wiki/images/7/78/VTK-Quadrature-Point-Design-Doc.pdf</a><br>
                            The ctest,
                            VTK/Filters/General/Testing/Cxx/TestQuadraturePoints.cxx,
                            could be used as an example.
                            <div>
                              <div><br>
                                <br>
                                <div>On 11/27/2013 02:32 PM, Marios
                                  Mavros wrote:<br>
                                </div>
                              </div>
                            </div>
                            <blockquote type="cite">
                              <div>
                                <div>
                                  <div dir="ltr">Hi&nbsp;
                                    <div><br>
                                    </div>
                                    <div>I have wrote a simple program
                                      in Fortran that transform the
                                      output of a finite element
                                      software in vtk Legacy Format. I
                                      don't know how to handle the Gauss
                                      points values. For example in my
                                      case my cells have 4 Gauss points
                                      and I have 4 values (for example
                                      strain in x-direction) for each
                                      cell. How I have to write the vtk
                                      file taking into account that each
                                      cell has many Gauss points?</div>
                                    <div><br>
                                    </div>
                                    <div>Thank you</div>
                                    <div><br>
                                    </div>
                                    <div>Marios &nbsp;&nbsp;</div>
                                  </div>
                                  <br>
                                  <fieldset></fieldset>
                                  <br>
                                </div>
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