.help imakw Sep86 imfort
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NAME
imakw -- add or set the value of an image header keyword
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SYNOPSIS
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subroutine imakwb (im, keyw, bval, comm, ier)
subroutine imakwc (im, keyw, cval, comm, ier)
subroutine imakwi (im, keyw, ival, comm, ier)
subroutine imakwr (im, keyw, rval, comm, ier)
subroutine imakwd (im, keyw, dval, comm, ier)

integer		im		#I image descriptor of open image
character*(*)	keyw		#I name of the keyword to be set
character*(*)	comm		#I comment string describing keyword
integer		ier		#O status return

logical		bval		#I logical (boolean) keyword value
character*(*)	cval		#I character string keyword value
integer		ival		#I integer keyword value
real		rval		#I real keyword value
doubleprecision	dval		#I double precision keyword value
.fi
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DESCRIPTION
The \fIimakw\fR procedures are used to set the values of image header keywords.
If the named keyword does not already exist, a new keyword of the indicated
datatype is first added and then the value of the new keyword is set,
otherwise the value of the existing keyword is updated.
The comment string is used only if a new keyword is created.
Automatic datatype conversion is provided when updating the value of
an existing keyword, i.e., if the keyword already exists there is some
flexibility in the choice of the datatype of the \fIimakw\fR procedure
to be used.
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RETURN VALUE
A zero status is returned if the named keyword exists, is writable, and if
the datatype coercion implied is permissible, or if the named keyword is
not found but can be added.

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SYS_IDBOVFL:	out of space in image header
SYS_IDBREDEF:	attempt to redefine an image header keyword
SYS_IDBTYPE:	illegal header parameter data type conversion
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SEE ALSO
imaddk, imacck, impkw, imgkw
.endhelp