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Procedure: agsm2gse
Purpose:
Converts between aberrated GSM coordinates and GSE coordinates
Inputs:
in_data: structure containing data to be transformed in AGSM coordinates
Output:
out_data: structure containing the transformed data in GSE 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 GSE coordinates
is in a standard tplot variable named 'position_agsm'.
get_data, 'position_agsm', data=position_agsm
; 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
agsm2gse, position_agsm, gse_pos_from_angle, rotation_angle=4.0
option 2:
; do the transformation to aberrated GSM (aGSM) using solar wind velocity loaded from OMNI
agsm2gse, position_agsm, gse_pos_from_vel, sw_velocity = [[Vx_data.Y], [Vy_data.Y], [Vz_data.Y]]
$LastChangedBy: egrimes $
$LastChangedDate: 2018-02-05 14:11:03 -0800 (Mon, 05 Feb 2018) $
$LastChangedRevision: 24646 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/cotrans/agsm2gse.pro $
(See general/cotrans/agsm2gse.pro)
procedure: cotrans, name_in, name_out [, time]
Purpose: geophysical coordinate transformations
GEI<-->GSE;
GSE<-->GSM;
GSM<-->SM;
GEI<-->GEO;
GEO<-->MAG;
GEI<-->J2000;
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
/GEI2J2000
/J20002GEI
/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: 2015-09-22 08:59:06 -0700 (Tue, 22 Sep 2015) $
$LastChangedRevision: 18869 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/cotrans/cotrans.pro $
(See general/cotrans/cotrans.pro)
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)
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!! $URL $
(See general/cotrans/cotrans_lib.pro)
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!!
(See general/cotrans/cotrans_lib.pro)
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!!
(See general/cotrans/cotrans_lib.pro)
procedure: subGSM2SM Purpose: transforms data from GSM to SM INPUTS: TIMES as time_struct, DATA_in as nx3 array keywords: Example: Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
procedure: subSM2GSM Purpose: transforms data from SM to GSM INPUTS: TIMES as time_struct, DATA_in as nx3 array keywords: Example: Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
procedure: subGEI2GEO Purpose: transforms data from GEI to GEO INPUTS: TIMES as time_struct, DATA_in as nx3 array keywords: Example: Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
procedure: subGEO2GEI Purpose: transforms data from GEO to GEI INPUTS: TIMES as time_struct, DATA_in as nx3 array keywords: Example: Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
procedure: subGEO2MAG Purpose: transforms data from GEO to MAG INPUTS: TIMES as time_struct, DATA_in as nx3 array keywords: Example: Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
procedure: subMAG2GEO Purpose: transforms data from MAG to GEO INPUTS: TIMES as time_struct, DATA_in as nx3 array keywords: Example: Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
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!!
(See general/cotrans/cotrans_lib.pro)
pro sub_GSE2aGSM
Purpose: transforms data from GSE to aberrated GSM coordinates
keywords:
/aGSM2GSE : inverse transformation
Example:
sub_GSE2aGSM,tha_fglc_gse,tha_fglc_agsm
sub_GSE2aGSM,tha_fglc_agsm,tha_fglc_gse,/aGSM2GSE
Notes: Same as sub_GSE2GSM, with "aberrated GSM" in the output message. The actual aberration
occurs in the higher level routine, gse2agsm
$LastChangedBy: nikos $
$LastChangedDate: 2025-02-27 20:48:10 -0800 (Thu, 27 Feb 2025) $
$LastChangedRevision: 33158 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/cotrans/cotrans_lib.pro $
(See general/cotrans/cotrans_lib.pro)
procedure: tgeigse_vect
Purpose: GEI to GSE transformation
(vectorized version of tgeigse from ROCOTLIB by
Patrick Robert)
Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
procedure: tgsegei_vect
Purpose: GSE to GEI transformation
(vectorized version of tgsegei from ROCOTLIB by
Patrick Robert)
Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
procedure: tgsegsm_vect
Purpose: GSE to GSM transformation
(vectorized version of tgsegsm from ROCOTLIB by
Patrick Robert)
Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
procedure: tgsmgse_vect
Purpose: GSM to GSE transformation
(vectorized version of tgsmgse from ROCOTLIB by
Patrick Robert)
Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
procedure: tgsmsm_vect
Purpose: GSM to SM transformation
(vectorized version of tgsmsma from ROCOTLIB by
Patrick Robert)
Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
procedure: tsmgsm_vect
Purpose: SM to GSM transformation
(vectorized version of tsmagsm from ROCOTLIB by
Patrick Robert)
Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
procedure: cdipdir_vect Purpose: calls cdipdir from ROCOTLIB in a vectorized environment Notes: under construction!!; faster algorithm (for loop across all points avoided) Hannes 05/25/2007 $URL $
(See general/cotrans/cotrans_lib.pro)
procedure: cdipdir Purpose: cdipdir from ROCOTLIB. direction of Earth's magnetic axis in GEO Notes: under construction!!
(See general/cotrans/cotrans_lib.pro)
PROCEDURE cotrans_lib
Loads the cotrans_lib library and sets configurations.
USAGE
Call cotrans_lib at the beginning of any routine
that needs to use any cotrans_lib routines, to ensure
that they are compiled. Configurations are valid until the next call
to cotrans_lib.
KEYWORDS
/nolimit_igrf configure cotrans_lib to remove the arbitrary
5-year limit on extrapolation of IGRF model.
This also isolates dprint code.
NOTE: the configuration will be reset
to 0 if cotrans_lib is called without keywords. This is
for backwards compatibility: any routine that calls
cotrans_lib without keywords will get the standard behavior,
regardless of how cotrans_lib was previously configured.
Note: Use this keyword at your own risk - extrapolating
these coefficients too far into the future can produce
non-physical results
Written by Hannes Leinweber
Modified by Ken Bromund: added /nolimit_igrf configuration
(See general/cotrans/cotrans_lib.pro)
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
(See general/cotrans/cotrans_lib.pro)
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!!
(See general/cotrans/cotrans_lib.pro)
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!!
(See general/cotrans/cotrans_lib.pro)
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:
(See general/cotrans/cotrans_lib.pro)
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:
(See general/cotrans/cotrans_lib.pro)
proceddure: subGEI2J2000 Purpose: transforms data from GEI TOD to J2000 INPUTS: TIMES as time_struct, DATA_in as nx3 array keywords: Example:
(See general/cotrans/cotrans_lib.pro)
procedure: subJ20002GEI Purpose: transforms data from J2000 to GEI TOD INPUTS: TIMES as time_struct, DATA_in as nx3 array keywords: Example:
(See general/cotrans/cotrans_lib.pro)
pro: sub_GEI2J2000 Purpose: transforms data from GEI to J2000 keywords: /J20002GEI : inverse transformation
(See general/cotrans/cotrans_lib.pro)
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!!
(See general/cotrans/cotrans_lib.pro)
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)
NAME:
geo2mag
PURPOSE:
Convert from geographic to geomagnetic coordinates
CALLING SEQUENCE:
geo2mag, data_in, data_out, time
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:
if data_in is a tplot variable:
IDL> geo2mag, data_in, data_out
otherwise:
IDL> geo2mag, data_in, data_out, time
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)
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: 2018-02-05 14:11:03 -0800 (Mon, 05 Feb 2018) $
$LastChangedRevision: 24646 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/cotrans/gse2agsm.pro $
(See general/cotrans/gse2agsm.pro)
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/trunk/general/cotrans/hdz2geo.pro $
(See general/cotrans/hdz2geo.pro)
NAME:
mag2geo.pro
PURPOSE:
Convert from geomagnetic to geographic coordinates
CALLING SEQUENCE:
mag2geo, data_in, data_out, time
INPUT:
data_in = an [n,3] element array of position data in km and in
MAG coordinates or a tplot variable
time = an n-element array containing double precision time values
corresponding to the points in data_in
KEYWORD INPUTS:
None
OUTPUT:
data_out = an [n,3] element array of position data in km in
newly transformed GEO coordinates
EXAMPLE:
if data_in is a tplot variable:
IDL> mag2geo, data_in, data_out
otherwise:
IDL> mag2geo, data_in, data_out, time
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)
FUNCTION:
sm2mlt
PURPOSE:
Converts a Cartesian vector in SM coordinates to Magnetic Local Time (MLT)
$LastChangedBy: egrimes $
$LastChangedDate: 2016-01-21 13:42:42 -0800 (Thu, 21 Jan 2016) $
$LastChangedRevision: 19770 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/cotrans/sm2mlt.pro $
(See general/cotrans/sm2mlt.pro)
Procedure: spd_cotrans_update_dlimits Purpose: This routine will replace coordinate plot labels only in the dlimits. If the coordinate name is clearly delineated, so that it will not accidentally modify substrings that look like coordinate names Notes: $LastChangedBy: egrimes $ $LastChangedDate: 2016-10-27 12:25:53 -0700 (Thu, 27 Oct 2016) $ $LastChangedRevision: 22221 $ $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/cotrans/spd_cotrans_update_dlimits.pro $
(See general/cotrans/spd_cotrans_update_dlimits.pro)
Procedure: spd_cotrans_validate_transform Purpose: Helper function to call when moving to/from non-inertial frames. A warning is printed if the variables metadata denotes it as a velocity. Notes: $LastChangedBy: aaflores $ $LastChangedDate: 2015-12-08 21:21:58 -0800 (Tue, 08 Dec 2015) $ $LastChangedRevision: 19549 $ $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/cotrans/spd_cotrans_validate_transform.pro $
(See general/cotrans/spd_cotrans_validate_transform.pro)
SPD_GET_NUT_ANGLES_VEC
Vectorized version of spd_get_nut_angles from spd_gei2j2000.pro
History:
2016-02-10 - Optimized to reduce memory spike for large data sets
(combined a few lines and added temporary() calls)
$LastChangedBy: aaflores $
$LastChangedDate: 2016-02-10 12:59:53 -0800 (Wed, 10 Feb 2016) $
$LastChangedRevision: 19928 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/cotrans/spd_get_nut_angles_vec.pro $
(See general/cotrans/spd_get_nut_angles_vec.pro)
SPD_MAKE_J2000_MATRIX_VEC Vectorized version0 of spd_make_j2000_matrix_vec from spd_gei2j2000.pro $LastChangedBy: nikos $ $LastChangedDate: 2018-06-11 13:13:02 -0700 (Mon, 11 Jun 2018) $ $LastChangedRevision: 25346 $ $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/cotrans/spd_make_j2000_matrix_vec.pro $
(See general/cotrans/spd_make_j2000_matrix_vec.pro)
Procedure:
spd_set_coord
Purpose:
Set coordinates of tplot variable
Calling Sequence:
spd_set_coord, tplotnames, coord
Input:
tplotnames: List of tplot variables
coord: New coordinate system, e.g. 'gse', 'gsm'
If not defined "unknown" will be used
Output:
none, alters dlimits.data_att.coord_sys
Notes:
$LastChangedBy: aaflores $
$LastChangedDate: 2016-05-25 18:14:39 -0700 (Wed, 25 May 2016) $
$LastChangedRevision: 21213 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/cotrans/spd_set_coord.pro $
(See general/cotrans/spd_set_coord.pro)
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)
PROCEDURE:
tgsm2mlt
PURPOSE:
Allows a user to convert position data in a tplot variable
into a tplot variable containing MLT data
INPUT:
in_varname: tplot name of position variable in GSM coordinates
out_varname: name of the tplot variable to store the MLT data in
KEYWORDS:
mlat: name of the tplot variable to store the magnetic latitude data in
NOTES:
Works on MMS position variables loaded from FGM files (which
include the magnitude of the vector as the 4-th component)
$LastChangedBy: egrimes $
$LastChangedDate: 2016-01-21 14:59:30 -0800 (Thu, 21 Jan 2016) $
$LastChangedRevision: 19772 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/general/cotrans/tgsm2mlt.pro $
(See general/cotrans/tgsm2mlt.pro)