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Last modified: Fri Nov 9 16:37:03 2007.


Directory Listing of Routines


Routine Descriptions

FAC_CRIB

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Procedure: fac_crib

Purpose:  A crib on showing how to transform into field aligned coordinates

Notes:

 $LastChangedBy: pcruce $
 $LastChangedDate: 2007-09-07 16:53:14 -0700 (Fri, 07 Sep 2007) $
 $LastChangedRevision: 1560 $
 $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/ssl_general/tags/tdas_3_00/cotrans/special/fac/fac_crib.pro $

(See ssl_general/cotrans/special/fac/fac_crib.pro)


FAC_MATRIX_MAKE

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Procedure: fac_matrix_make

Purpose:  generates a field aligned coordinate transformation matrix
from an input B vector array(and sometimes a position vector array)
then stores it in a tplot variable
Arguments:
   mag_var_name=the name of the tplot variable storing the magnetic field
   vectors to be used in transformation matrix generation
   pos_var_name(optional)=the name of the tplot variable storing the position
   vectors to be used in transformation matrix generation
   newname(optional)=the name of the tplot variable in which to store
   the output
   error(optional) = named variable that holds the error state of the 
   computation 1 = success 0 = failure
   other_dim(optional) = the second axis for the field aligned
   coordinate system.
   ************For all transformations Z = B************

   valid second coord(other_dim) options:

         'Xgse', translates from gse or gsm into FAC
                    Definition(works on GSE or GSM):
                    X Axis = on plane defined by Xgse - Z
                    Second coordinate definition: Y = Z x X_gse
                    Third coordinate, X completes orthogonal RHS
                    (right hand system) triad: XYZ
         'Rgeo',translate from geo into FAC using radial posision vector
                    R_pos is radial position vector, radialy inwards.
                    Second coordinate definition: Y = Z x Rpos
                    Third coordinate, X completes orthogonal RHS XYZ.
         'Ygeo', translate from geo into FAC using azimuthal position vector
                    Y_pos is the azimuthal position vector, positive Westward
                    Second coordinate definition: Y = Z x Y_pos
                    Third coordinate, X completes orthogonal RHS XYZ
         'Ysm', translate from geo into FAC using azimuthal sm position
                 Y Axis = on plane defined by Phi_sm- Z
                 Second coordinate definition: X = Phi_sm x Z
                 Third completes orthogonal RHS XYZ
 Example:
  fac_matrix_make,'tha_fgs',other_dim='Xgse',pos_var_name='tha_pos',out_var_name='tha_fgs_fac_mat'

Notes:--> I'm a little sparse on comments here, but I think the code
should be self documenting

(See ssl_general/cotrans/special/fac/fac_matrix_make.pro)