# 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
petscmatfactorinfosize.h
petscmat.h
petscmatinfosize.h
petscmatmod.F90