HELP · SEE_ALSO

## 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.