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    <p>Yes, just mesh the set of (u,v) coordinates corresponding to your
      (x,y,z) reference points.</p>
    <p>S.<br>
    </p>
    <div class="moz-cite-prefix">Le 20/11/2020 à 13:05, P M a écrit :<br>
    </div>
    <blockquote type="cite"
cite="mid:CACf7ODv1_uePeq8YMZRUT=-XhXuVrxZKjcEGgn6Sk4-LEqLngA@mail.gmail.com">
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        <div>I guess I do have such an u-v-plane.</div>
        <div><br>
        </div>
        <div>The background of the background :</div>
        <div><br>
        </div>
        <div>The task is to map an image onto a 3D geometry.<br>
        </div>
        <div><br>
        </div>
        <div>The image includes reference points, which correspond to
          known x-y-z coordinates.<br>
        </div>
        <div><br>
        </div>
        <div>So the image plane is (my guess) the u-v-plane.</div>
        <div><br>
        </div>
        <div>BR</div>
        <div>Philipp<br>
        </div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div><br>
        </div>
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      <br>
      <div class="gmail_quote">
        <div dir="ltr" class="gmail_attr">Am Fr., 20. Nov. 2020 um
          12:16 Uhr schrieb Stéphane Mottelet <<a
            href="mailto:stephane.mottelet@utc.fr"
            moz-do-not-send="true">stephane.mottelet@utc.fr</a>>:<br>
        </div>
        <blockquote class="gmail_quote" style="margin:0px 0px 0px
          0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
          <div>
            <p>In order to use mesh2d with your data, there must exist a
              plane (u,v) on which you could project your (x,y,z) data.
              The mesh obtained on projected data (u,v) would give you
              the triangulation of the (x,z,y) data. This won't be
              possible with mesh2d if you take for example scattered
              points on a sphere. However, any non-linear transformation
              "unfolding" the data could also help to use pure 2d tools
              like mesh2d.<br>
            </p>
            <p>S.<br>
            </p>
            <div>Le 20/11/2020 à 12:05, P M a écrit :<br>
            </div>
            <blockquote type="cite">
              <div dir="ltr">
                <div dir="ltr"><br>
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                <br>
                <div class="gmail_quote">
                  <div dir="ltr" class="gmail_attr">Am Fr., 20. Nov.
                    2020 um 11:47 Uhr schrieb Stéphane Mottelet <<a
                      href="mailto:stephane.mottelet@utc.fr"
                      target="_blank" moz-do-not-send="true">stephane.mottelet@utc.fr</a>>:<br>
                  </div>
                  <blockquote class="gmail_quote" style="margin:0px 0px
                    0px 0.8ex;border-left:1px solid
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                    <div>
                      <p>Hi again,<br>
                      </p>
                      <div>Le 20/11/2020 à 11:30, P M a écrit :<br>
                      </div>
                      <blockquote type="cite">
                        <div dir="ltr">
                          <div>OK,</div>
                          <div>some more background:</div>
                          <div><br>
                          </div>
                          <div>I actually want to perform a delaunay
                            triangulation on a set of X-Y-Z-coordinates.</div>
                        </div>
                      </blockquote>
                      I suppose you mean a triangulation of scattered
                      X-Y-Z but you call mesh2d with X-Y only ?<br>
                    </div>
                  </blockquote>
                  <div><br>
                  </div>
                  <div>Yes, indeed. And there is the bug in my data.</div>
                  <div>As x-y coordinates repeat, they do have a
                    different z in the original data.</div>
                  <div>But since I call mesh2d with x-y only there are
                    indeed identical points.<br>
                  </div>
                  <div><br>
                  </div>
                  <div> </div>
                  <blockquote class="gmail_quote" style="margin:0px 0px
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                    <div>
                      <blockquote type="cite">
                        <div dir="ltr">
                          <div><br>
                          </div>
                          <div>I know of CGLAB, but it seems only
                            available to Scilab 6.0.x, while I am on
                            Scilab 6.1.0</div>
                        </div>
                      </blockquote>
                      CGLAB is based on a very old version of CGAL and
                      thus is very hard  to maintain as is. There is a
                      lot of work...<br>
                    </div>
                  </blockquote>
                  <div><br>
                  </div>
                  <div>I am currently installing Scilab 6.0 to try
                    CGLAB... <br>
                  </div>
                  <blockquote class="gmail_quote" style="margin:0px 0px
                    0px 0.8ex;border-left:1px solid
                    rgb(204,204,204);padding-left:1ex">
                    <div>
                      <blockquote type="cite">
                        <div dir="ltr">
                          <div><br>
                          </div>
                          <div>So the nearest thing to a delaunay
                            triangulation I found is mesh2d...</div>
                        </div>
                      </blockquote>
                      Yeah. Suboptimal choice indeed...<br>
                      <blockquote type="cite">
                        <div dir="ltr">
                          <div>Because of the delaunay triangulation, I
                            am not sure if the order of points may
                            change.<br>
                          </div>
                        </div>
                      </blockquote>
                      What do you mean ?<br>
                    </div>
                  </blockquote>
                  <div><br>
                  </div>
                  <div>The scattered points represent a 3D surface
                    geometry.</div>
                  <div>If the points will be resorted, I could imagine
                    that the triangulation does not fit to the surface
                    geometry anymore.<br>
                  </div>
                  <blockquote class="gmail_quote" style="margin:0px 0px
                    0px 0.8ex;border-left:1px solid
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                    <div>
                      <blockquote type="cite">
                        <div dir="ltr">
                          <div><br>
                          </div>
                          <div>About unique:</div>
                          <div><br>
                          </div>
                          <div>The result I get is actual of same size
                            as the input matrix...I therefore do assume
                            that each point is unique in the first place
                            (which they actually should).</div>
                          <div><br>
                          </div>
                          <div>What does repeat are individual x, y, z
                            coordinates, but in different combinations.</div>
                          <div>So the actual point is different.</div>
                          <div><br>
                          </div>
                          <div><br>
                          </div>
                          <div>e.g.:    x may repeat, but than the
                            y-z-coordinates are different from point to
                            point</div>
                        </div>
                      </blockquote>
                      <p>Could you share the data (you can send me a
                        private message) ?<br>
                      </p>
                      <p>S.<br>
                      </p>
                      <blockquote type="cite">
                        <div dir="ltr">
                          <div> <br>
                          </div>
                          <div>Thanks,</div>
                          <div>Philipp<br>
                          </div>
                          <div>
                            <div><br>
                            </div>
                            <div><br>
                            </div>
                          </div>
                        </div>
                        <br>
                        <div class="gmail_quote">
                          <div dir="ltr" class="gmail_attr">Am Fr., 20.
                            Nov. 2020 um 10:57 Uhr schrieb Stéphane
                            Mottelet <<a
                              href="mailto:stephane.mottelet@utc.fr"
                              target="_blank" moz-do-not-send="true">stephane.mottelet@utc.fr</a>>:<br>
                          </div>
                          <blockquote class="gmail_quote"
                            style="margin:0px 0px 0px
                            0.8ex;border-left:1px solid
                            rgb(204,204,204);padding-left:1ex">
                            <div>
                              <p>Hi Philipp,</p>
                              <p>Glad to hear that some people use
                                mesh2d. I know we have to improve the
                                error message by getting the numbers at
                                the Fortran level... There is also other
                                errors which are not easy to fix without
                                knowing the number of the problematic
                                point (point too close to the boundary,
                                for example). Can you file a bug on BZ ?</p>
                              <p>S.<br>
                              </p>
                              <div>Le 20/11/2020 à 10:03, P M a écrit :<br>
                              </div>
                              <blockquote type="cite">
                                <div dir="ltr">
                                  <div>Dear all,</div>
                                  <div><br>
                                  </div>
                                  <div>using the mesh2d - function I get
                                    an error:     mesh2di: some points
                                    are identical.</div>
                                  <div><br>
                                  </div>
                                  <div><br>
                                  </div>
                                  <div>How to identify these points and
                                    remove the duplicates?</div>
                                  <div><br>
                                  </div>
                                  <div>There are roughly 500'000
                                    coordinates....</div>
                                  <div><br>
                                  </div>
                                  <div>Thank you,</div>
                                  <div>Philipp<br>
                                  </div>
                                </div>
                                <br>
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                              <pre cols="72">-- 
Stéphane Mottelet
Ingénieur de recherche
EA 4297 Transformations Intégrées de la Matière Renouvelable
Département Génie des Procédés Industriels
Sorbonne Universités - Université de Technologie de Compiègne
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Ingénieur de recherche
EA 4297 Transformations Intégrées de la Matière Renouvelable
Département Génie des Procédés Industriels
Sorbonne Universités - Université de Technologie de Compiègne
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Tel : +33(0)344234688
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Stéphane Mottelet
Ingénieur de recherche
EA 4297 Transformations Intégrées de la Matière Renouvelable
Département Génie des Procédés Industriels
Sorbonne Universités - Université de Technologie de Compiègne
CS 60319, 60203 Compiègne cedex
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Stéphane Mottelet
Ingénieur de recherche
EA 4297 Transformations Intégrées de la Matière Renouvelable
Département Génie des Procédés Industriels
Sorbonne Universités - Université de Technologie de Compiègne
CS 60319, 60203 Compiègne cedex
Tel : +33(0)344234688
<a class="moz-txt-link-freetext" href="http://www.utc.fr/~mottelet">http://www.utc.fr/~mottelet</a>
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