General conventions

• For GRID subroutines it is normal to assume that the input grid object would pass GRIDMAN_GRID_CHECK
• For INDEX subroutines it is normal to assume that the input index would pass GRIDMAN_INDEX_CHECK
• For GRID2D subroutines it is normal to assume that the input grid object would pass GRIDMAN_GRID2D_CHECK

Per default, integrity of input data structures is NOT checked. To enforce checks use set GRIDMAN_CHECK=.TRUE.

All text messages from all subroutines are aprinted into unit defined by GRIDMAN_UNIT

Extra debugging output is enforced by setting GRIDMAN_DBG=.TRUE.

In case of abnormal termination (IERR>0) the data structures and arrays which have to be created inside the subroutine are returned in clean (deallocated) state