Nodes of different colours represent the following:
Solid arrows point from a procedure to one which it calls. Dashed
arrows point from an interface to procedures which implement that interface.
This could include the module procedures in a generic interface or the
implementation in a submodule of an interface in a parent module.
PURE FUNCTION minkowski_sqnorm(u)RESULT(sqnorm)IMPLICIT NONEDOUBLE PRECISION,DIMENSION(4),INTENT(IN)::u(0:3)DOUBLE PRECISION::sqnormsqnorm=minkowski_inner_product(u,u)END FUNCTION minkowski_sqnorm