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    <p>Re:</p>
    <p>I'am currently going through the code.<br>
    </p>
    <p>Thans<br>
    </p>
    <div class="moz-cite-prefix">On 16/02/2022 16:47, Junchao Zhang
      wrote:<br>
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    <blockquote type="cite"
cite="mid:CA+MQGp-wD-SQ39BXm0+GW1nh_58AcrecbtX7-w1en4zOR2JEFQ@mail.gmail.com">
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      <div dir="ltr"><a
href="https://gitlab.com/petsc/petsc/-/blob/main/src/vec/is/sf/tests/ex9.c"
          moz-do-not-send="true" class="moz-txt-link-freetext">https://gitlab.com/petsc/petsc/-/blob/main/src/vec/is/sf/tests/ex9.c</a>
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              <div dir="ltr">--Junchao Zhang</div>
            </div>
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          <br>
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      <br>
      <div class="gmail_quote">
        <div dir="ltr" class="gmail_attr">On Wed, Feb 16, 2022 at 9:40
          AM Medane TCHAKOROM <<a
            href="mailto:medane.tchakorom@univ-fcomte.fr"
            moz-do-not-send="true" class="moz-txt-link-freetext">medane.tchakorom@univ-fcomte.fr</a>>
          wrote:<br>
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            <p>Re:</p>
            <p><br>
            </p>
            <p>Sorry, but I can't find this file in my installation.
              I'am using Petsc 3.14.2</p>
            <p><br>
            </p>
            <p>Thanks<br>
            </p>
            <div>On 16/02/2022 16:00, Junchao Zhang wrote:<br>
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            <blockquote type="cite">
              <div dir="ltr">We could still do it. See the example at 
                petsc/src/vec/is/sf/tests/ex9.c
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                    <div dir="ltr">
                      <div dir="ltr">--Junchao Zhang</div>
                    </div>
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                  <br>
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              <br>
              <div class="gmail_quote">
                <div dir="ltr" class="gmail_attr">On Wed, Feb 16, 2022
                  at 8:47 AM Medane TCHAKOROM <<a
                    href="mailto:medane.tchakorom@univ-fcomte.fr"
                    target="_blank" moz-do-not-send="true"
                    class="moz-txt-link-freetext">medane.tchakorom@univ-fcomte.fr</a>>
                  wrote:<br>
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                    <p>Re:</p>
                    <p><br>
                    </p>
                    <p>It does not apply, because "<span>their
                        communicator must be on the same set of
                        processes" .</span></p>
                    <p>In my case, I have two disjoint subcomm from
                      PETSC_COMM_WORD with same number of processes.<br>
                    </p>
                    <p>I want to send information (Petsc Vec) from one
                      subcomm to another subcomm.</p>
                    <p>Thanks<br>
                    </p>
                    <div>On 16/02/2022 15:43, Junchao Zhang wrote:<br>
                    </div>
                    <blockquote type="cite">
                      <div dir="ltr">See Notes at <a
href="https://petsc.org/main/docs/manualpages/PetscSF/VecScatterCreate.html"
                          target="_blank" moz-do-not-send="true"
                          class="moz-txt-link-freetext">https://petsc.org/main/docs/manualpages/PetscSF/VecScatterCreate.html</a>
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                        <div>Does it apply to your case?  </div>
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                            <div dir="ltr">
                              <div dir="ltr">--Junchao Zhang</div>
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                          <br>
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                      <br>
                      <div class="gmail_quote">
                        <div dir="ltr" class="gmail_attr">On Wed, Feb
                          16, 2022 at 8:12 AM Medane TCHAKOROM <<a
                            href="mailto:medane.tchakorom@univ-fcomte.fr"
                            target="_blank" moz-do-not-send="true"
                            class="moz-txt-link-freetext">medane.tchakorom@univ-fcomte.fr</a>>
                          wrote:<br>
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                            <p>Re:</p>
                            <p>I forgot to mention that the nodes are in
                              differents communicators. Does VecScatter
                              functionnality still applies ?</p>
                            <p>Thanks.<br>
                            </p>
                            <div>On 16/02/2022 15:03, Matthew Knepley
                              wrote:<br>
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                            <blockquote type="cite">
                              <div dir="ltr">
                                <div dir="ltr">On Wed, Feb 16, 2022 at
                                  8:55 AM Medane TCHAKOROM <<a
                                    href="mailto:medane.tchakorom@univ-fcomte.fr"
                                    target="_blank"
                                    moz-do-not-send="true"
                                    class="moz-txt-link-freetext">medane.tchakorom@univ-fcomte.fr</a>>
                                  wrote:<br>
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                                  <blockquote class="gmail_quote"
                                    style="margin:0px 0px 0px
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                                    rgb(204,204,204);padding-left:1ex">Hello,<br>
                                    <br>
                                    I want to pass a Petsc Vec from one
                                    node to another one. Is there any <br>
                                    Petsc method for doing this<br>
                                  </blockquote>
                                  <div><br>
                                  </div>
                                  <div>You likely want the VecScatter
                                    functionality. There is a discussion
                                    of this in the manual: <a
href="https://petsc.org/main/docs/manual/vec/?highlight=vecscatter#sec-unstruct"
                                      target="_blank"
                                      moz-do-not-send="true"
                                      class="moz-txt-link-freetext">https://petsc.org/main/docs/manual/vec/?highlight=vecscatter#sec-unstruct</a></div>
                                  <div><br>
                                  </div>
                                  <div>  Thanks,</div>
                                  <div><br>
                                  </div>
                                  <div>    Matt</div>
                                  <div> </div>
                                  <blockquote class="gmail_quote"
                                    style="margin:0px 0px 0px
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                                    or should I use MPI_Irecv and
                                    MPI_Isend for non-blocking
                                    communication ?<br>
                                    <br>
                                    When using MPI_Isend, can i send a
                                    Petsc Vec, or should I get the array
                                    <br>
                                    from it, and then send it ?<br>
                                    <br>
                                    Thanks<br>
                                    <br>
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                                            <div>What most experimenters
                                              take for granted before
                                              they begin their
                                              experiments is infinitely
                                              more interesting than any
                                              results to which their
                                              experiments lead.<br>
                                              -- Norbert Wiener</div>
                                            <div><br>
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                                            <div><a
                                                href="http://www.cse.buffalo.edu/~knepley/"
                                                target="_blank"
                                                moz-do-not-send="true">https://www.cse.buffalo.edu/~knepley/</a><br>
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