The opposite process, of resetting the history component to an undefined state, may be performed using the NDF_RESET routine with a component name of `History', thus:
CALL NDF_RESET( INDF, 'History', STATUS )
This has the effect of rendering the history component undefined and of deleting all the information it contains. Because this operation is irreversible and destroys all previous history information, it is performed only if explicitly requested. In particular, the history component remains unaffected when a ``wild-card'' component name of `' is given to NDF_RESET, or when an existing NDF is opened for `WRITE' access (circumstances in which other NDF components are normally automatically reset).
A less drastic method of disabling history recording while retaining
earlier information is controlled by the history update mode
which is described in §.