routine copies the supplied input NDF
, performing a specified trigonometric operation
(sine, tangent, etc.
) on each value in the DATA array. The VARIANCE
present, is modified appropriately. Pixels for which the required value is undefined,
or outside the numerical range of the NDFs data type, are set bad in the output.
trig in trigfunc out title
IN = NDF (Read)
OUT = NDF (Write)
The output NDF structure.
Trigonometrical function to be applied. The options are as
"ACOS" –- arc-cosine (radians)
"ACOSD" –- arc-cosine (degrees)
"ASIN" –- arc-sine (radians)
"ASIND" –- arc-sine (degrees)
"ATAN" –- arc-tangent (radians)
"ATAND" –- arc-tangent (degrees)
"COS" –- cosine (radians)
"COSD" –- cosine (degrees)
"SIN" –- sine (radians)
"SIND" –- sine (degrees)
"TAN" –- tangent (radians)
"TAND" –- tangent (degrees)
TITLE = LITERAL (Read)
for the output
NDF. A null value will cause the title of the NDF supplied for Parameter IN
to be used instead.
trig sindata asind data Take the
arc-sine of the data values in the NDF called sindata, and store the results (in
degrees) in the NDF called data.
trig sindata asin data As above, but
the output values are stored in radians.
This routine correctly processes the AXIS, DATA, QUALITY, LABEL, TITLE, UNITS,
HISTORY, WCS, and VARIANCE components of an NDF data structure and propagates all
Processing of bad pixels and automatic quality masking are supported.
All non-complex numeric data types can be handled. Arithmetic is performed
using single-precision floating point, or double precision, if appropriate,
but the numeric type of the input pixels is preserved in the output NDF.