<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html > <head><title>psb_init — Initializes PSBLAS parallel environment</title> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <meta name="generator" content="TeX4ht (http://www.tug.org/tex4ht/)"> <meta name="originator" content="TeX4ht (http://www.tug.org/tex4ht/)"> <!-- html,3 --> <meta name="src" content="userhtml.tex"> <link rel="stylesheet" type="text/css" href="userhtml.css"> </head><body > <!--l. 7--><div class="crosslinks"><p class="noindent">[<a href="userhtmlsu61.html" >next</a>] [<a href="userhtmlsu55.html#tailuserhtmlsu57.html">tail</a>] [<a href="userhtmlsu59.html#userhtmlsu60.html" >up</a>] </p></div> <h4 class="subsectionHead"><span class="titlemark">7.1 </span> <a id="x69-1060007.1"></a>psb_init — Initializes PSBLAS parallel environment</h4> <div class="verbatim" id="verbatim-61"> call psb_init(ctxt, np, basectxt, ids) </div> <!--l. 11--><p class="nopar" > <!--l. 13--><p class="indent" > This subroutine initializes the PSBLAS parallel environment, defining a virtual parallel machine. <dl class="description"><dt class="description"> <span class="cmbx-10">Type:</span> </dt><dd class="description">Synchronous. </dd><dt class="description"> <span class="cmbx-10">On Entry</span> </dt><dd class="description"> </dd><dt class="description"> <span class="cmbx-10">np</span> </dt><dd class="description">Number of processes in the PSBLAS virtual parallel machine.<br class="newline" />Scope: <span class="cmbx-10">global</span>.<br class="newline" />Type: <span class="cmbx-10">optional</span>.<br class="newline" />Intent: <span class="cmbx-10">in</span>.<br class="newline" />Specified as: an integer value.  Default: use all available processes. </dd><dt class="description"> <span class="cmbx-10">basectxt</span> </dt><dd class="description">the initial communication context. The new context will be defined from the processes participating in the initial one.<br class="newline" />Scope: <span class="cmbx-10">global</span>.<br class="newline" />Type: <span class="cmbx-10">optional</span>.<br class="newline" />Intent: <span class="cmbx-10">in</span>.<br class="newline" />Specified as: an integer value.  Default: use MPI_COMM_WORLD. </dd><dt class="description"> <span class="cmbx-10">ids</span> </dt><dd class="description">Identities of the processes to use for the new context; the argument is ignored when <span class="obeylines-h"><span class="verb"><span class="cmtt-10">np</span></span></span> is not specified. This allows the processes in the new environment to be in an order different from the original one.<br class="newline" />Scope: <span class="cmbx-10">global</span>.<br class="newline" />Type: <span class="cmbx-10">optional</span>.<br class="newline" />Intent: <span class="cmbx-10">in</span>.<br class="newline" />Specified as: an integer array.  Default: use the indices (0<span class="cmmi-10">…</span><span class="cmmi-10">np </span><span class="cmsy-10">- </span>1).</dd></dl> <!--l. 42--><p class="indent" > <dl class="description"><dt class="description"> <span class="cmbx-10">On Return</span> </dt><dd class="description"> </dd><dt class="description"> <span class="cmbx-10">ctxt</span> </dt><dd class="description">the communication context identifying the virtual parallel machine, type <span class="obeylines-h"><span class="verb"><span class="cmtt-10">psb_ctxt_type</span></span></span>. Note that this is always a duplicate of <span class="obeylines-h"><span class="verb"><span class="cmtt-10">basectxt</span></span></span>, so that library communications are completely separated from other communication operations.<br class="newline" />Scope: <span class="cmbx-10">global</span>.<br class="newline" />Type: <span class="cmbx-10">required</span>.<br class="newline" />Intent: <span class="cmbx-10">out</span>.<br class="newline" />Specified as: an integer variable.</dd></dl> <!--l. 55--><p class="noindent" ><span class="cmbx-12">Notes</span> <ol class="enumerate1" > <li class="enumerate" id="x69-106002x1">A call to this routine must precede any other PSBLAS call. </li> <li class="enumerate" id="x69-106004x2">It is an error to specify a value for <span class="cmmi-10">np </span>greater than the number of processes available in the underlying base parallel environment.</li></ol> <!--l. 64--><div class="crosslinks"><p class="noindent">[<a href="userhtmlsu61.html" >next</a>] [<a href="userhtmlsu57.html" >front</a>] [<a href="userhtmlsu59.html#userhtmlsu60.html" >up</a>] </p></div> <!--l. 64--><p class="indent" > <a id="tailuserhtmlsu57.html"></a> </body></html>