Next: ACCESSING NDFS FOR OUTPUT
Up: Primitive Storage Form
Previous: Primitive Storage Form
A case which occasionally causes
problems can arise if a primitive NDF is created (e.g. by
calling NDF_CREP - see §
) and an array component is then
mapped for access using an access mode such as `WRITE/ZERO'.
This access mode will cause the component's bad-pixel flag to be set
to .FALSE. (see §
).
When the component is unmapped, this, in turn, will cause its storage form
to be implicitly converted to simple.
This behaviour is correct, but it is not always what is expected, or wanted.
It can be avoided by setting the bad-pixel flag value back to
.TRUE. (see §
) before unmapping the
component concerned,
or by performing the initialisation to zero explicitly rather than via an
initialisation option on the mapping mode.
Next: ACCESSING NDFS FOR OUTPUT
Up: Primitive Storage Form
Previous: Primitive Storage Form
Starlink User Note 33
R.F. Warren-Smith
11th January 2000
E-mail:rfws@star.rl.ac.uk
Copyright © 2000 Council for the Central Laboratory of the Research Councils