NAME

tacarrousel -- Perform target acquisition carrousel calibration.

USAGE

tacarrousel intable outtable

DESCRIPTION

This task performs the carrousel calibration for a Goddard High Resolution Spectrograph (GHRS) target acquisition mode. The input to this task is a table of target acquisition image diode positions calculated as a function of carrousel position. A least squares fit is performed giving the coefficients of the polynomial, this gives the diode position as a function of carrousel position.

PARAMETERS

intable [file name]

Name of the input table containing tabulated carrousel positions and diode positions. This table is normally generated by the tadiodepos task and must have the following columns:

     'CARPOS'   - Carrousel position (double).
     'X_CENTER' - Diode position (double).

This table must also have the table header parameters GRATING and APERTURE.

outtable [file name]

Name of the output table that is to contain the fitted coefficients. This table has the following columns:

     'GRATING'   - Target acquisition mode (MIRROR-A1, MIRROR-A2, 
                   MIRROR-N1 or MIRROR-N2) as read from the header 
                   of the input table (char*9).
     'APERTURE'  - Aperture name read from the header of the
		   input table (char*3).
     'COEF_0', 'COEF_1', 'COEF_2', 'COEF_3', and 'COEF_4' 
		 - Polynomial coefficients (double).
     'RMS_OF_FIT - RMS of the residuals of the fit (in diode
		   units) (double).

(order = 1) [integer, min=1, max=3]

The order of the polynomial to fit.

EXAMPLES

1. Fit the results in table diodepos and put the results in a new table named george.

   cl> tacarrousel diodepos george

2. Repeat with a second order polynomial:

  cl> tacarrousel diodepos george order=2

BUGS

REFERENCES

HELP

For assistance using this or any other tasks, please contact help@stsci.edu or call the help desk at 410-338-1082.

SEE ALSO

tadiodepos