$LastChangedDate: 27-Juil-2011 $

# CL_fr_G502terMat

Gamma50 (Veis) to terrestrial frame transformation matrix

## Calling Sequence

       M=CL_fr_G502terMat(cjd[,ut1_utc])

## Description

- Computes the frame transformation matrix M from Gamma50 (Veis) to the terrestrial ("Earth fixed") reference frame.

  By convention, M multiplied by coordinates relative to G50 yields coordinates relative to the terrestrial frame.

- Notes:

  Transformation from Gamma50 (Veis) to terrestrial frame consists in a single rotation of the Veis sideral time (see CL_mod_sidTimeG50) around the Z axis.

- See Reference Frames for more details on the definition of reference frames.

## Parameters

cjd:

  modified julian day from 1950.0 (UTC) (1xN)

ut1_utc :

  (optional) ut1-utc [seconds] (default is 0) (1xN)

M:

  Gamma50 (Veis) to terrestrial frame transformation matrix (3x3xN)

## Authors

- CNES - DCT/SB

## Bibliography

- 1) CNES - MSLIB FORTRAN 90, Volume R (mr_tsid_veis)

## See also

- CL_fr_ter2J2000Mat

- CL_fr_G502ter

- CL_fr_ter2G50

- CL_mod_sidTimeG50

- CL_fr_H0n2J2000Mat

## Examples

    // Conversion G50 to terrestrial
    pos_G50 = [[3500.e3;2500.e3;5800.e3] , [4500.e3;2100.e3;6800.e3]];
    cjd = [21010 , 21011];
    M = CL_fr_G502terMat(cjd);
    pos_ter = M * (pos_G50);
    pos_ter = CL_fr_G502ter(cjd,pos_G50);

    // Conversion terrestrial to G50
    pos_ter_sph = [[0;%pi/4;%CL_eqRad+700.e3],[0;0;%CL_eqRad+800.e3]];
    pos_ter = CL_co_sph2car(pos_ter_sph);
    cjd = [21010 , 21011];
    M = CL_fr_G502terMat(cjd);
    pos_G50 = M' * (pos_ter);
    pos_G50 = CL_fr_ter2G50(cjd,pos_ter);