# Matrix Operations (Mat)

PETSc matrices (`Mat` objects) are used to store Jacobians and other sparse matrices
in PDE-based (or other) simulations.  Users guide chapter: [](ch_matrices). See also [](../MatGraphOperations/index).

<A HREF="../../../src/mat/tutorials/index.html">Examples</A><BR>

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Source files
<p><a href="matreg.c.html">matreg.c</a><br>
<a href="matregis.c.html">matregis.c</a><br>
<a href="dlregismat.c.html">dlregismat.c</a><br>
<a href="matnull.c.html">matnull.c</a><br>
<a href="matrix.c.html">matrix.c</a><br>
<a href="matproduct.c.html">matproduct.c</a><br>

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Directories
<p><a href="ftn-custom/index.html">ftn-custom</a><br>
<a href="f90-custom/index.html">f90-custom</a><br>