AIPS HELP file for COWINDOW in 31DEC22
As of Tue May 30 12:35:05 2023
COWINDOW: Verb to set window centered on a coordinate
INNAME Image name(name).
INCLASS Image name(class).
INSEQ 0.0 9999.0 Image name(seq. #). 0=>high
INDISK 0.0 9.0 Disk drive #. 0=>any
COORDINA Coordinate in image
IMSIZE 0.0 8192.0 X,Y size to include
0=>entire centered image
BLC @ 0.0 4096.0 Pixel location (X,Y,...) in
@ image of lower left corner.
TRC @ 0.0 4096.0 Pixel location (X,Y,...) in
@ image of upper right corner.
Use: To set values in the adverbs BLC and TRC so that a subarray of an
image centered on a particular X,Y coordinate will be selected.
INNAME.....Image name(name). Standard defaults.
INCLASS....Image name(class). Standard defaults.
INSEQ......Image name(seq. #). 0 => highest.
INDISK.....Disk drive # of image. 0 => any.
COORDINA...The X and Y coordinates are found as:
Xpos = abs(CO(1)) + abs(CO(2))/60 + abs(CO(3))/3600
if any of CO(1), CO(2), CO(3) < 0: Xpos = -Xpos
Ypos = abs(CO(4)) + abs(CO(5))/60 + abs(CO(6))/3600
if any of CO(4), CO(5), CO(6) < 0: Ypos = -Ypos
Note that, although these are most suited to RA, Dec in
sexagesimal notation, they can be used for any type of
coordinate. The units are standard FITS units (e.g
degrees, m/sec, Hz, sec, etc.) except that right
ascensions are in hours of time.
IMSIZE.....Maximum size of image to select in X and Y. The image will
be centered on the coordinate so the actual IMSIZE(i) used
will be the lesser of IMSIZE(i) and the distance in the
i'th coordinate to the nearer edge of the image. Note
that an even value of IMSIZE(i) cannot be centered upon a
pixel, so IMSIZE(i)+1 is used.
0 -> 16384 (i.e. use the nearest edge size).
BLC........Bottom left corner of set window in pixel coordinates; only
the first two values are changed. BLC(3)-BLC(7) are used
to set the depth into the image which may affect the
first two coordinate values.
TRC........Upper right corner of set window in pixel coordinates; only
the first two values are changed.