Subsetting: how to cut out parts from a
Frequently one does not want to download the whole coverage, but only part of it.
Such a subset always
is a coverage again, and actually keeps all other characteristics unchanged, beyond
its reduced extent.
Actually there are two different variants of subsetting:
- trimming a
coverage extracts a cutout along the axis
indicated, specified by a lower and upper bound on this axis. Obviously, as we
talk about subsetting,
the new interval limits must lie inside the original coverage's domain.
- slicing a
coverage extracts a slice (mathematicians
would call this a hyperplane) from a given coverage along one of its
axes, thereby reducing
dimension by one. Again, the slicing point must lie within the original