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Directory Listing of Routines

Routine Descriptions

COTRANS

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procedure: cotrans, name_in, name_out [, time]

Purpose: geophysical coordinate transformations

         GEI<-->GSE;
         GSE<-->GSM;
         GSM<-->SM;
         GEI<-->GEO;
         GEO<-->MAG;
         interpolates the spinphase, right ascension, declination
         updates coord_sys attribute of output tplot variable.

inputs

   name_in 	... data in the input coordinate system (t-plot variable name, 
                                                        or array)
   name_out    ... variable name for output            (t-plot variable name,
                                                        or array)
   time        ... optional input: array of times for input values, if provided
                   then the first parameter is an array, and the second
                   parameter is a named variable to contain the output array.


keywords:
   TRANSFORMATIONS


	/GEI2GSE
	/GSE2GEI

	/GSE2GSM
	/GSM2GSE

 /GSM2SM
 /SM2GSM

 /GEI2GEO
 /GEO2GEI

 /GEO2MAG
 /MAG2GEO

 /IGNORE_DLIMITS: set so it won't require the coordinate
system of the input tplot variable to match the coordinate
system from which the data is being converted

Examples:


      cotrans,'tha_fgl_gse','tha_fgl_gsm',/GSE2GSM
      cotrans,'tha_fgl_gsm','tha_fgl_gse',/GSM2GSE

      cotrans,'tha_fgl_gse','tha_fgl_gei',/GSE2GEI
      cotrans,'tha_fgl_gei','tha_fgl_gse',/GEI2GSE

      cotrans,'tha_fgl_gsm','tha_fgl_sm',/GSM2SM
      cotrans,'tha_fgl_sm','tha_fgl_gsm',/SM2GSM

Notes: under construction!!
       clrussell, 03-30-12, added GEO2MAG and MAG2GEO conversions

Written by: Hannes Schwarzl & Patrick Cruce(pcruce@igpp.ucla.edu)

 $LastChangedBy: egrimes $
 $LastChangedDate: 2013-09-26 10:11:07 -0700 (Thu, 26 Sep 2013) $
 $LastChangedRevision: 13153 $
 $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_1_00/general/cotrans/cotrans.pro $

(See general/cotrans/cotrans.pro)

COTRANS_GET_COORD

 [Previous Routine] [Next Routine] [List of Routines] 
	Function: COTRANS_GET_COORD

	Purpose:  determine the coordinate system of data by 
                 examining the contents of it's DLIMIT structure.

	Calling Sequence:
		tplot_var = 'tha_eff'
		get_data, tplot_var, data=d, limit=l, dlimit=dl
		coord = cotrans_get_coord( dl) 
               ; -- or --
               coord = cotrans_get_coord('tha_eff')

	Arguements:
		DL, Anonymous STRUCT, or tplot variable name.

	Notes:
		None.

 $LastChangedBy: kenb-mac $
 $LastChangedDate: 2007-05-01 15:11:55 -0700 (Tue, 01 May 2007) $
 $LastChangedRevision: 622 $
 $URL $

(See general/cotrans/cotrans_get_coord.pro)

COTRANS_LIB[10]

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procedure: subSM2GSM

Purpose: transforms data from SM to GSM

INPUTS: TIMES as time_struct, DATA_in as nx3 array


keywords:

Example:


Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[11]

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procedure: subGEI2GEO

Purpose: transforms data from GEI to GEO

INPUTS: TIMES as time_struct, DATA_in as nx3 array


keywords:

Example:


Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[12]

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procedure: subGEO2GEI

Purpose: transforms data from GEO to GEI

INPUTS: TIMES as time_struct, DATA_in as nx3 array


keywords:

Example:


Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[13]

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procedure: subGEO2MAG

Purpose: transforms data from GEO to MAG

INPUTS: TIMES as time_struct, DATA_in as nx3 array


keywords:

Example:


Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[14]

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procedure: subMAG2GEO

Purpose: transforms data from MAG to GEO

INPUTS: TIMES as time_struct, DATA_in as nx3 array


keywords:

Example:


Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[15]

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procedure: csundir_vect

Purpose: calculates the direction of the sun
         (vectorized version of csundir from ROCOTLIB by
          Patrick Robert)

INPUTS: integer time


output :      gst      greenwich mean sideral time (radians)
              slong    longitude along ecliptic (radians)
              sra      right ascension (radians)
              sdec     declination of the sun (radians)
              obliq    inclination of Earth's axis (radians)



Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[16]

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: tgeigse_vect

Purpose: GEI to GSE transformation
         (vectorized version of tgeigse from ROCOTLIB by
          Patrick Robert)



Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[17]

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: tgsegei_vect

Purpose: GSE to GEI transformation
         (vectorized version of tgsegei from ROCOTLIB by
          Patrick Robert)



Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[18]

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: tgsegsm_vect

Purpose: GSE to GSM transformation
         (vectorized version of tgsegsm from ROCOTLIB by
          Patrick Robert)



Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[19]

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: tgsmgse_vect

Purpose: GSM to GSE transformation
         (vectorized version of tgsmgse from ROCOTLIB by
          Patrick Robert)



Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[1]

 [Previous Routine] [Next Routine] [List of Routines] 
pro sub_GSE2GSM

Purpose: transforms data from GSE to GSM


keywords:
   /GSM2GSE : inverse transformation
Example:
      sub_GSE2GSM,tha_fglc_gse,tha_fglc_gsm

      sub_GSE2GSM,tha_fglc_gsm,tha_fglc_gse,/GSM2GSE


Notes: under construction!!  will run faster in the near future!!

Written by Hannes Schwarzl
 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_1_00/general/cotrans/cotrans_lib.pro $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[20]

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: tgsmsm_vect

Purpose: GSM to SM transformation
         (vectorized version of tgsmsma from ROCOTLIB by
          Patrick Robert)



Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[21]

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: tsmgsm_vect

Purpose: SM to GSM transformation
         (vectorized version of tsmagsm from ROCOTLIB by
          Patrick Robert)



Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[22]

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: cdipdir_vect

Purpose: calls cdipdir from ROCOTLIB in a vectorized environment



Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $

 faster algorithm (for loop across all points avoided) Hannes 05/25/2007

 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[23]

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: cdipdir

Purpose: cdipdir from ROCOTLIB. direction of Earth's magnetic axis in GEO



Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[2]

 [Previous Routine] [Next Routine] [List of Routines] 
pro: sub_GEI2GSE

Purpose: transforms THEMIS fluxgate magnetometer data from GEI to GSE


keywords:
   /GSE2GEI : inverse transformation
Example:
      sub_GEI2GSE,tha_fglc_gei,tha_fglc_gse

      sub_GEI2GSE,tha_fglc_gse,tha_fglc_gei,/GSE2GEI


Notes: under construction!!  will run faster in the near future!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[2]

 [Previous Routine] [Next Routine] [List of Routines] 
pro sub_GSM2SM

Purpose: transforms data from GSM to SM


keywords:
   /SM2GSM : inverse transformation
Example:
      sub_GSM2SM,tha_fglc_gsm,tha_fglc_sm

      sub_GSM2SM,tha_fglc_sm,tha_fglc_gsm,/SM2GSM


Notes: under construction!!  will run faster in the near future!!

Written by Hannes Schwarzl
 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_1_00/general/cotrans/cotrans_lib.pro $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[3]

 [Previous Routine] [Next Routine] [List of Routines] 
pro sub_GEI2GEO

Purpose: transforms data from GEI to GEO


keywords:
   /GEO2GEI : inverse transformation
Example:
      sub_GEI2GEO,tha_fglc_gei,tha_fglc_geo

      sub_GEI2GEO,tha_fglc_geo,tha_fglc_gei,/GEO2GEI


Notes:

Written by Patrick Cruce(pcruce@igpp.ucla.edu)
 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_1_00/general/cotrans/cotrans_lib.pro $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[4]

 [Previous Routine] [Next Routine] [List of Routines] 
pro sub_GEO2MAG

Purpose: transforms data from GEO to MAG


keywords:
   /MAG2GEO : inverse transformation
Example:
      sub_GEO2MAG,tha_fglc_geo,tha_fglc_mag

      sub_GEO2MAG,tha_fglc_mag,tha_fglc_geo,/MAG2GEO


Notes:

Written by Cindy Russell(clrussell@igpp.ucla.edu)
 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_1_00/general/cotrans/cotrans_lib.pro $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[5]

 [Previous Routine] [Next Routine] [List of Routines] 
proceddure: subGEI2GSE

Purpose: transforms data from GEI to GSE

INPUTS: TIMES as time_struct, DATA_in as nx3 array


keywords:

Example:


Notes: under construction!!  will run faster in the near future!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[6]

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: subGSE2GEI

Purpose: transforms data from GSE to GEI

INPUTS: TIMES as time_struct, DATA_in as nx3 array


keywords:

Example:


Notes: under construction!!  will run faster in the near future!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[7]

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: subGSE2GSM

Purpose: transforms data from GSE to GSM

INPUTS: TIMES as time_struct, DATA_in as nx3 array


keywords:

Example:


Notes: under construction!!  will run faster in the near future!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[8]

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: subGSM2GSE

Purpose: transforms data from GSM to GSE

INPUTS: TIMES as time_struct, DATA_in as nx3 array


keywords:

Example:


Notes: under construction!!  will run faster in the near future!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_LIB[9]

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: subGSM2SM

Purpose: transforms data from GSM to SM

INPUTS: TIMES as time_struct, DATA_in as nx3 array


keywords:

Example:


Notes: under construction!!

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:47:19 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14435 $
 $URL $

(See general/cotrans/cotrans_lib.pro)

COTRANS_SET_COORD

 [Previous Routine] [Next Routine] [List of Routines] 
	Function: COTRANS_SET_COORD

	Purpose:  set the coordinate system of data by 
                 setting the data_att structure of its DLIMIT structure.

	Calling Sequence:
		tplot_var = 'tha_eff'
		get_data, tplot_var, data=d, limit=l, dlimit=dl
		coord = cotrans_set_coord, dl, 'gei'
		store_data, tplot_var, data=d, limit=l, dlimit=dl

	Arguements:
		DL, Anonymous STRUCT.

	Notes:
		None.

 $LastChangedBy: kenb-mac $
 $LastChangedDate: 2007-08-01 22:08:30 -0700 (Wed, 01 Aug 2007) $
 $LastChangedRevision: 1318 $
 $URL $

(See general/cotrans/cotrans_set_coord.pro)

GEO2MAG

 [Previous Routine] [Next Routine] [List of Routines] 
 NAME:
       geo2mag

 PURPOSE:
       Convert from geographic to geomagnetic coordinates

 CALLING SEQUENCE:
       geo2mag, time, data_in, data_out

 INPUT:
       time = an array [n] of double precision time in seconds from 1970-Jan-01/00:00:00.000
       data_in = an array [n,3] of position data in km. in GEO coordinates or a tplot variable

 KEYWORD INPUTS:
       None

 OUTPUT:
       data_out = an array [n,3] of the input data in MAG coordinates                    

 EXAMPLE:

       IDL> geo2mag, data_in data_out      

 NOTES:

       The algorithm and rotational matrices were developed by Pascal Saint-Hilaire 
       (Saint-Hilaire@astro.phys.ethz.ch), May 2002

 MODIFICATION HISTORY:

(See general/cotrans/geo2mag.pro)

GSE2AGSM

 [Previous Routine] [Next Routine] [List of Routines] 
 Procedure: gse2agsm

 Purpose: 
      Converts between GSE coordinates and aberrated GSM coordinates

 Inputs:
      in_data: structure containing data to be transformed in GSE coordinates
   
 Output: 
      out_data: structure containing the transformed data in aberrated GSM coordinates
   
 Keywords:
      sw_velocity (optional): vector containing solar wind velocity data, [Vx, Vy, Vz] in GSE coordinates
      rotation_angle (optional): angle to rotate about the Z axis to point into the solar wind (degrees)


 Notes:
     Either the solar wind velocity (/sw_velocity) or rotation angle (/rotation_angle) keyword
     needs to be defined to do the transformation
      
 Examples:
    In the following example, the data to be transformed into aGSM coordinates 
      is in a standard tplot variable named 'position_gse'. 
    
    get_data, 'position_gse', data=position_gse
     
    ; load solar wind velocity data using OMNI (GSE coordinates, km/s)
    omni_hro_load, varformat=['Vx', 'Vy', 'Vz']
    
    ; remove NaNs from the solar wind velocity
    tdeflag, ['OMNI_HRO_1min_Vx', 'OMNI_HRO_1min_Vy', 'OMNI_HRO_1min_Vz'], 'remove_nan'

    ; get the IDL structures containing the velocity components
    get_data, 'OMNI_HRO_1min_Vx_deflag', data=Vx_data
    get_data, 'OMNI_HRO_1min_Vy_deflag', data=Vy_data
    get_data, 'OMNI_HRO_1min_Vz_deflag', data=Vz_data
    
    option 1:
        ; do the transformation to aberrated GSM (aGSM) using a rotation angle
        gse2agsm, position_gse, agsm_pos_from_angle, rotation_angle=4.0
    
    option 2:
        ; do the transformation to aberrated GSM (aGSM) using solar wind velocity loaded from OMNI
        gse2agsm, position_gse, agsm_pos_from_vel, sw_velocity = [[Vx_data.Y], [Vy_data.Y], [Vz_data.Y]]
    

 $LastChangedBy: egrimes $
 $LastChangedDate: 2014-02-25 15:48:12 -0800 (Tue, 25 Feb 2014) $
 $LastChangedRevision: 14436 $
 $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_1_00/general/cotrans/gse2agsm.pro $

(See general/cotrans/gse2agsm.pro)

HDZ2GEO

 [Previous Routine] [Next Routine] [List of Routines] 
procedure: hdz2geo

Purpose: Coordinate transformation between HDZ coordinates & GEO coordinates

     HDZ is defined as:

       H = horizontal field strength, in the plane formed by Z and GEO graphic north
       D = field strength in the Z x X direction in nT
       Z = downward field strength  
       
     H should be a projection onto a basis vector pointing north from station in nT
     D should be a projection onto a basis vector perpendicular to H in the horizontal plane.
         
     Total field strength should be sqrt(H^2+D^2+Z^2) not sqrt(H^2+Z^2)
     D must be in nT not degrees
    
     GEO is defined as:
         X = Vector parallel to vector pointing outward at the intersection of the equatorial plane and the 0 degree longitudinal meridean(Greenwich Meridean)
         Y = Z x X
         Z = Vector parallel to orbital Axis of Earth Pointing northward.

inputs:

  data_in: 
    Name of input tplot variable to be transformed, or Nx3 array of data for transformation. If no tplot variable is specific latitude and longitude must be set.
  data_out:
    Name of tplot variable in which to store output.  If this is a named variable and not a string, output data will instead be returned in variable.
  latitude: latitude of the HDZ station, must be set if data_in is not tplot variable, or latitude and longitude not stored in dlimit.data_att or dlimit.cdf.vatt 
  longitude: longitude of the HDZ station, must be set if data_in is not tplot variable, or latitude and longitude not stored in dlimit.data_att or dlimit.cdf.vatt
  geo2hdz: If set, performs inverse transformation from GEO to HDZ
  error: Set to named variable that will return 1 if an error occurs and 0 otherwise
  rotation_matrix:  Returns the rotation matrix that will be used to transform
  
keywords:

   /SSE2GSE inverse transformation

   /IGNORE_DLIMITS: Dlimits normally used to determine if coordinate
   system is correct, to decide if position needs offset, or to 
   stop incorrect transforms.  This option will stop this behavior. 

Examples:
  hdz2geo,hdz_arr_in,geo_arr_out,latitude=60.4,longitude=173.6
  hdz2geo,'in_tvar_name_hdz','out_tvar_name_geo'
  hdz2geo,'in_tvar_name_geo','out_tvar_name_hdz',/geo2hdz  ;inverse transformation

Notes:
   #1 HDZ coordinates only make sense relative to a location, assumedly a ground station(gmag)
   
   #2 Specific latitude and longitude keywords must be set if: 
    (1) data_in is not a tplot variable name 
    -OR-
    (2) tplot variable named by data_in does not specific site_latitude & site_longitude in dlimits 
   
   #3 If latitude or longitude keywords are set, these values will be used, not dlimit values. 
   
   #4 This transformation is a first order approximation.  It treats the earth as if it is a true sphere, ignoring
   distortions due to the fact that the earth is actually an oblate spheroid.  
  
   
   Written by Patrick Cruce(pcruce@igpp.ucla.edu)

 $LastChangedBy: pcruce $
 $LastChangedDate: 2010-03-29 15:27:35 -0700 (Mon, 29 Mar 2010) $
 $LastChangedRevision: 7445 $
 $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_1_00/general/cotrans/hdz2geo.pro $

(See general/cotrans/hdz2geo.pro)

MAG2GEO.PRO

 [Previous Routine] [Next Routine] [List of Routines] 
 NAME:
      mag2geo.pro

 PURPOSE:
     Convert from geomagnetic to geographic coordinates

 CALLING SEQUENCE:
       mag2geo, time, data_in, data_out

 INPUT:
       data_in = an [n,3] element array of position data in km and in
                MAG coordinates

 KEYWORD INPUTS:
               None

 OUTPUT:
       data_in = an [n,3] element array of position data in km in
                 newly transformed GEO coordinates

 EXAMPLE:

       IDL> geo2mag, data_in data_out      

 NOTES:

       The algorithm and rotational matrices were developed by Pascal Saint-Hilaire 
       (Saint-Hilaire@astro.phys.ethz.ch), May 2002

 MODIFICATION HISTORY:

(See general/cotrans/mag2geo.pro)

SPG2SSL

 [Previous Routine] [List of Routines] 
procedure: spg2ssl

Purpose: coordinate transformation

         SPG<-->SSL;


inputs

	name_thx_xxx_in 	... data in the input coordinate system (t-plot variable name)
   name_thx_xxx_out    ... name for output  (t-plot variable name)

keywords:

   probe :  explicitly specify a probe, rather than inferring from tplot name

   TRANSFORMATIONS

   /SSL2SPG inverse transformation

   /IGNORE_DLIMITS if the specified from coord is different from the
coord system labeled in the dlimits structure of the tplot variable
setting this keyword prevents an error

Example:
      spg2ssl,'tha_fgl_spg','tha_fgl_ssl'
      spg2ssl,'tha_fgl_ssl','tha_fgl_spg',/SSL2SPG
Notes: under construction!!

Written by Hannes Schwarzl
 $LastChangedBy: kenb-mac $
 $LastChangedDate: 2007-05-05 10:29:05Z $
 $LastChangedRevision: 645 $
 $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/ssl_general/trunk/cotrans/ssl2dsl.pro $

(See general/cotrans/spg2ssl.pro)