INDF1 = INTEGER (Given)

CLIST = CHARACTER $\ast$ ( $\ast$ ) (Given)

PLACE = INTEGER (Given and Returned)

INDF2 = INTEGER (Returned)

STATUS = INTEGER (Given and Returned)

• If this routine is called with STATUS set, then a value of NDF__NOID will be returned for the INDF2 argument, although no further processing will occur. The same value will also be returned if the routine should fail for any reason. In either event the placeholder will still be annulled. The NDF__NOID constant is defined in the include file NDF_PAR.

• The components whose values are to be propagated (copied) from the existing NDF to the new data structure are specified via the CLIST argument. Thus CLIST=’DATA,QUALITY’ would cause the DATA and QUALITY components to be propagated (if available) from the existing NDF to the new structure, in addition to those propagated by default. Component propagation may be suppressed by supplying a component name with the prefix ’NO’. Thus CLIST=’DATA,NOHISTORY’ would propagate the DATA component, but suppress propagation of HISTORY. If component names appear more than once in the CLIST value, then the last occurrence takes precedence.

• Propagation of specific NDF extensions may be suppressed by using ’NOEXTENSION()’ as one of the items in the CLIST argument; a list of the extensions to be suppressed should appear between the parentheses. Thus CLIST=’AXIS,NOEXTENSION(IRAS,ASTERIX)’ would propagate the AXIS component, but suppress propagation of the IRAS and ASTERIX extensions (if present). Propagation of suppressed extensions may be re-enabled by specifying ’EXTENSION()’ in a similar manner at a later point in the CLIST value.

• An asterisk ($\ast$) may be used as a wild card to match all extension names. Thus ’NOEXTENSION($\ast$),EXTENSION(IRAS)’ may be used to indicate that only the IRAS extension should be propagated.

• Whether or not a named extension is propagated by default can be controlled via an NDF tuning parameter (see NDF_TUNE). The defaults established using NDF_TUNE can be over-ridden by specifying the extension explicitly within the CLIST parameter; e.g. ’EXTENSION(FITS)’ or ’NOEXTENSION(FITS)’ can be used to over-ride the default established by the PXTFITS tuning parameter.

• Component names in the CLIST argument may be abbreviated to 3 characters, but extension names must appear in full.