  We present a brief tutorial on the nuts and bolts computation of a
multisymplectic particle-in-cell algorithm using the discretized Lagrangian
approach. This approach, originated by Marsden, Shadwick, and others, brings
the benefits of symplectic integration of Hamiltonian systems to full
electromagnetic particle-in-cell algorithms. To make the work more
approachable, we present a basic discussion of the philosophy, combined with a
detailed derivation of a standard 1-dimensional electrostatic particle-in-cell
algorithm.
