subtracts one NDF
data structure from another pixel-by-pixel to produce a new NDF.
sub in1 in2 out
IN1 = NDF (Read)
First NDF, from which the
second NDF is to be subtracted.
IN2 = NDF (Read)
Second NDF, to be subtracted from
the first NDF.
OUT = NDF (Write)
Output NDF to contain the difference of the two
TITLE = LITERAL (Read)
The title for the output NDF. A null
value will cause the title of the NDF supplied for Parameter IN1 to be used
sub a b c This subtracts the NDF called b from
the NDF called a, to make the NDF called c. NDF c inherits its title from a.
sub out=c in1=a in2=b title="Background subtracted" This subtracts the
NDF called b from the NDF called a, to make the NDF called c. NDF c has the
If the two input NDFs have different
pixel-index bounds, then they will be trimmed to match before being subtracted. An
error will result if they have no pixels in common.