1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML3.2 EN">
<HTML>
<HEAD> <link rel="canonical" href="http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/Mat/MatMPIAIJSetPreallocationCSR.html" />
<META NAME="GENERATOR" CONTENT="DOCTEXT">
<TITLE>MatMPIAIJSetPreallocationCSR</TITLE>
</HEAD>
<BODY BGCOLOR="FFFFFF">
<div id="version" align=right><b>petsc-3.7.5 2017-01-01</b></div>
<div id="bugreport" align=right><a href="mailto:petsc-maint@mcs.anl.gov?subject=Typo or Error in Documentation &body=Please describe the typo or error in the documentation: petsc-3.7.5 v3.7.5 docs/manualpages/Mat/MatMPIAIJSetPreallocationCSR.html "><small>Report Typos and Errors</small></a></div>
<A NAME="MatMPIAIJSetPreallocationCSR"><H1>MatMPIAIJSetPreallocationCSR</H1></A>
Allocates memory for a sparse parallel matrix in AIJ format (the default parallel PETSc format).
<H3><FONT COLOR="#CC3333">Synopsis</FONT></H3>
<PRE>
#include "petscmat.h"
PetscErrorCode MatMPIAIJSetPreallocationCSR(Mat B,const PetscInt i[],const PetscInt j[], const PetscScalar v[])
</PRE>
Collective on <A HREF="../Sys/MPI_Comm.html#MPI_Comm">MPI_Comm</A>
<P>
<H3><FONT COLOR="#CC3333">Input Parameters</FONT></H3>
<TABLE border="0" cellpadding="0" cellspacing="0">
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>B </B></TD><TD>- the matrix
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>i </B></TD><TD>- the indices into j for the start of each local row (starts with zero)
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>j </B></TD><TD>- the column indices for each local row (starts with zero)
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>v </B></TD><TD>- optional values in the matrix
</TD></TR></TABLE>
<P>
<P>
<H3><FONT COLOR="#CC3333">Notes</FONT></H3>
The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
thus you CANNOT change the matrix entries by changing the values of a[] after you have
called this routine. Use <A HREF="../Mat/MatCreateMPIAIJWithSplitArrays.html#MatCreateMPIAIJWithSplitArrays">MatCreateMPIAIJWithSplitArrays</A>() to avoid needing to copy the arrays.
<P>
The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
<P>
The format which is used for the sparse matrix input, is equivalent to a
row-major ordering.. i.e for the following matrix, the input data expected is
as shown
<P>
<pre>
1 0 0
</pre>
<pre>
2 0 3 P0
</pre>
<pre>
-------
</pre>
<pre>
4 5 6 P1
</pre>
<pre>
</pre>
<pre>
Process0 [P0]: rows_owned=[0,1]
</pre>
<pre>
i = {0,1,3} [size = nrow+1 = 2+1]
</pre>
<pre>
j = {0,0,2} [size = 3]
</pre>
<pre>
v = {1,2,3} [size = 3]
</pre>
<pre>
</pre>
<pre>
Process1 [P1]: rows_owned=[2]
</pre>
<pre>
i = {0,3} [size = nrow+1 = 1+1]
</pre>
<pre>
j = {0,1,2} [size = 3]
</pre>
<pre>
v = {4,5,6} [size = 3]
</pre>
<P>
<H3><FONT COLOR="#CC3333">Keywords</FONT></H3>
matrix, aij, compressed row, sparse, parallel
<BR>
<P>
<H3><FONT COLOR="#CC3333">See Also</FONT></H3>
<A HREF="../Mat/MatCreate.html#MatCreate">MatCreate</A>(), <A HREF="../Mat/MatCreateSeqAIJ.html#MatCreateSeqAIJ">MatCreateSeqAIJ</A>(), <A HREF="../Mat/MatSetValues.html#MatSetValues">MatSetValues</A>(), <A HREF="../Mat/MatMPIAIJSetPreallocation.html#MatMPIAIJSetPreallocation">MatMPIAIJSetPreallocation</A>(), <A HREF="../Mat/MatCreateAIJ.html#MatCreateAIJ">MatCreateAIJ</A>(), MPIAIJ,
<BR><A HREF="../Mat/MatCreateSeqAIJWithArrays.html#MatCreateSeqAIJWithArrays">MatCreateSeqAIJWithArrays</A>(), <A HREF="../Mat/MatCreateMPIAIJWithSplitArrays.html#MatCreateMPIAIJWithSplitArrays">MatCreateMPIAIJWithSplitArrays</A>()
<P><B><P><B><FONT COLOR="#CC3333">Level:</FONT></B>developer
<BR><FONT COLOR="#CC3333">Location:</FONT></B><A HREF="../../../src/mat/impls/aij/mpi/mpiaij.c.html#MatMPIAIJSetPreallocationCSR">src/mat/impls/aij/mpi/mpiaij.c</A>
<BR><A HREF="./index.html">Index of all Mat routines</A>
<BR><A HREF="../../index.html">Table of Contents for all manual pages</A>
<BR><A HREF="../singleindex.html">Index of all manual pages</A>
</BODY></HTML>
|
