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rtransformx stsdas.hst_calib.foc.focgeom


NAME · USAGE · DESCRIPTION · PARAMETERS · EXAMPLES · BUGS · REFERENCES
SEE_ALSO

NAME

rtransformx -- Perform linear transformations on reseau mark coordinates.

USAGE

rtransformx input entry output action rota crota1 crota2 mag1 mag2 cmag1 cmag2 shift1 shift2

DESCRIPTION

This program performs linear transformations on the reseau mark coordinates, or on one or more entries in a reseau file. The reseau marks can be rotated, shifted, or magnified in any order.

Holes in the reseau file (identified by INDEF coordinates) are left unchanged.

PARAMETERS

input [file name]
File name of the reseau file used as input.
entry = * [string]
Entry name (or template) specifying which marks are to be transformed. The default is to process all entries.
output [file name]
File name for the output reseau file. The output and input file names must be different.
action [string, allowed values: r s m]
The action parameter accepts up to 3 letters, each of which specify an individual operation that will be performed on the reseau file. The value "s" will shift an image; the value "r" will rotate the image; and the value "m" will magnify the image. Actions are performed in the order specified in the command. The actions are not commutative, so you must pay attention to the order of operands passed to action. For example, passing the value "msr" to action will magnify, then shift, and then rotate.
rota = 0.[real]
The rotation angle in degrees counterclockwise from the center specified by crota1,'crota2'. The default is 0.0, but is ignored if r is not specified in the action parameter.
crota= 0.0 [real]
The X coordinate of the center of rotation.
crota= 0.0 [real]
The Y coordinate of the center of rotation.
mag= 1.0 [real]
Magnification factor along the X axis. This parameter is ignored if "m" is not specified in the action parameter.
mag= 1.0 [real]
Magnification factor along the Y axis. This parameter is ignored if "m" is not specified in the action parameter.
cmag= 0.0 [real]
The X coordinate of the center of magnification. This parameter is ignoreed if "m" is not specified in the action parameter.
cmag= 0.0 [real]
The Y coordinate of the center of magnification. This parameter is ignored if "m" is not specified in the action parameter.
shift= 0.0 [real]
The number to be added to the X coordinates in a shift operation. This parameter is ignored if "s" is not specified in the action parameter.
shift= 0.0 [real]
The number to be added to the Y coordinates in a shift operation. This parameter is ignored if "s" is not specified in the action parameter.

EXAMPLES

1. Rotate the image by 10 degrees around the center (512,512) and then increase the X coordinates by one pixel:

fo> rtransformx input * output "rs" 10 512 512 shift1=1 shift2=0

2. Suppose the coordinates in z.tab were measured on a "zoomed" image. Dezoom the coordinates and put the results in dz.tab.


fo> rtransformx z * dz "ms" mag1=2 mag2=1 cmag1=1 cmag2=0 \
    shift1=0.5 shift2=0

BUGS

REFERENCES

This task was written by David Giaretta.

SEE ALSO

Type "help focgeom option=sysdoc" for a higher-level description of the focgeom package.

Type "help reseau" for more information on reseau files.


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