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pxcoord stsdas.analysis.gasp



pxcoord -- List pixel coordinates of guide stars.


pxcoord image gsctable


List the pixel coordinates of objects in both a table and an image. The STSDAS table is assumed to be extracted from the Guide Star Catalog and the image is assumed to contain a coordinate transformations that Guide star positions are marked on an image by replacing pixels along a pair of lines near the pixel corresponding to the coordinate.

Coordinates are read from an STSDAS table containing right ascensions and declinations. Estimated pixel coordinates for each star are computed based on a transformation specified in task parameters. The pixel coordinates are written in table columns X_PIX and Y_PIX. If these columns are not present in the specified table, they are created. Pixel values used as the marker can be specified explicitly or can be based on the highest pixel value in the image.


inimage [file name]
Input image. Note that pixels are replaced in-place. We recommend using a copy of the image.
gsctable [file name]
Guide star catalog table.
pixval = INDEF [real]
Marker pixel value.
X coordinate at the reference pixel.
Y coordinate at the reference pixel.
crpix= 1 [real]
X reference pixel.
crpix= 1 [real]
Y reference pixel.
cdelt= 1 [real]
X coordinate increment per pixel.
cdelt= 1 [real]
Y coordinate increment per pixel.
crota = [real]
Rotation angle (in degrees).
ctype= "RA" [string]
X coordinate type.
ctype= "DEC" [string]
Y coordinate type.
valid = no [boolean]
Initialize all stars to valid?
xycoord = no [boolean]
Use (X,Y) pixel coordinates?
imtrans = yes [boolean]
Find the coordinate transformation in the input image?
pltsol = no [boolean]
Use the plate solution for the coordinate transformation?




extgst, intrep, targets

Type "help gasp opt=sys" for a description of the gasp package and the Guide Star Catalog.

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