# Programming with the Core Libraries

- LibOptions: globals, locals, has_changed and all that
  - Declaring Options
  - What is has_changed ?
  - Reading Options in Module
  - Handling Options in Driver
- Linear Algebra in PSI4
  - How to call BLAS & LAPACK in PSI4
    - BLAS Wrappers
    - Important BLAS Routines
    - LAPACK Wrappers
    - Important Lapack Routines
  - How to use low-level BLAS/LAPACK with `psi4.core.Matrix`
  - How to name orbital bases (e.g., AO & SO)
  - How to name orbital dimensions
  - How to name orbital spaces (e.g., docc)
    - Multireference Dimensions