说明：  ! 2 ! HOMPACK90 is a suite of FORTRAN 90 subroutines for solving nonlinear 3 ! systems of equations by homotopy methods. There are subroutines for 4 ! fixed point, zero finding, and general homotopy curve tracking problems, 5 ! utilizing both dense and sparse Jacobian matrices, and implementing 6 ! three different algorithms: ODE-based, normal flow, and augmented 7 ! Jacobian. The (driver) subroutines called by the user are given in the 8 ! table below, and are well documented internally. The user need not 9 ! be concerned with any other subroutines in HOMPACK90.