# 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 [](../MatOrderings/index).
Examples
interface/
impls/
tests/
tutorials/
utils/
matfd/
partition/
coarsen/
order/
color/
f90-mod/
ftn-kernels/