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Name: CALCULATE_LSHELL
Purpose: Calculates the l shell value given spacecraft position data in GSM coordinates
Inputs: Spacecraft position vector, an array of [time, x, y, z]
where time is double precision, and x, y, z, are in GSM coordinates and have units in RE
Outputs: The l shell value, or -1L on failure
Usage: lshell = calculate_lshell(pos_gsm_re)
See Also: tkm2re.pro, thm_crib_calculate_lshell.pro
History:
Notes: This routine requires IDL geopack routines, returns -1L if not installed
$LastChangedBy: jwl $
$LastChangedDate: 2021-07-28 18:16:15 -0700 (Wed, 28 Jul 2021) $
$LastChangedRevision: 30156 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_6_1/external/IDL_GEOPACK/calculate_lshell.pro $
(See external/IDL_GEOPACK/calculate_lshell.pro)
PROCEDURE: calc_pdyn
PURPOSE: This procedure calculates the solar wind dynamic pressure from proton speed and proton density, accounting for contributions from both
protons and alpha particles. Previous SPEDAS code only accounted for protons. OMNIweb provides a "Pressure" data set that assumes
f_alpha = N_a/N_p = 0.05, which according to Vassilis may be a little high. This routine accepts an f_alpha parameter, whicb defaults to 0.04.
INPUTS:
N_p: Solar wind ion density (rho) cm^-3
V_p: proton velocity (km/sec)
;
Returns:
Dynamic pressure in units of nPa, suitable for passing to GEOPACK field models
KEYWORDS:
speed(optional): set this if Vp_tvar is stored as a speed
Notes:
Derivation of Alpha particle pressure correction is here: https://omniweb.gsfc.nasa.gov/ftpbrowser/bow_derivation.html
$LastChangedBy: jwl $
$LastChangedDate: 2021-07-28 18:16:15 -0700 (Wed, 28 Jul 2021) $
$LastChangedRevision: 30156 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_6_1/external/IDL_GEOPACK/calc_pdyn.pro $
(See external/IDL_GEOPACK/calc_pdyn.pro)
PROCEDURE: get_tsy_params
PURPOSE: this procedure will interpolate inputs, generate
tsyganenko model parameters and store them in a tplot
variable that can be passed directly to the model
procedure
relevant variables can be loaded from
INPUTS: dst_tvar: tplot variable storing the dst index
imf_tvar: tplot variable name storing the interplanetary
magnetic field bvector in gsm
Np_tvar: tplot variable name storing the solar wind
ion density(rho) cm^-3
Vp_tvar: tplot variable name storing the proton velocity
model: a string, should be 'T96','T01', 'T04S', 'TS07', 'TA15B' or 'TA15N' (upper or
lower case)
KEYWORDS:
newname(optional): the name of the output tplot variable
(default: t96_par','t01_par' or 't04s_par' depending on
selected model)
trange(optional): the time range over which the parameters
should range, if not set, this program will check the
timespan variable or prompt the user for a range
speed(optional): set this if Vp_tvar is stored as a speed
imf_yz(optional): set this to indicate that the imf_tvar is actually storing
two separate tplot variables(the first being the y component
of the imf and the second being the z)
This can be done as follows:
store_data,'omni_imf',data=['OMNI_HRO_1min_BY_GSM','OMNI_HRO_1min_BZ_GSM']
Then just pass omni_imf into get_tsy_params and set /imf_yz
g_coefficients (optional): set this to specify a tplot variable containing the
G coefficients for the T01 field model. If this keyword is not set, Geopack
will calculate the G coefficients automatically. This keyword is ignored for
field models other than T01
w_coefficients (optional): set this to specify a tplot variable containing
the W coefficients for the Tsyganenko-Sitnov (04) field model. If this
keyword is not set, Geopack will calculate the W coefficients automatically.
This keyword is ignored for field models other than TS04
xind (optional): Set this to specify a tplot variable containing either the B-index
(for the TA15B model), or the N-index (for the TA15N model). If not supplied, it will
be calculated internally.
pressure_tvar (optional): Set this to specify a tplot variable containing solar wind dynamic pressure data.
If not supplied, it will be calculated internally from proton density and proton speed.
$LastChangedBy: jwl $
$LastChangedDate: 2022-09-22 15:32:22 -0700 (Thu, 22 Sep 2022) $
$LastChangedRevision: 31126 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_6_1/external/IDL_GEOPACK/get_tsy_params.pro $
(See external/IDL_GEOPACK/get_tsy_params.pro)
Function: igp_test
Purpose: Tests whether the idl/geopack module is installed
Provides installation message if not installed
Keywords:
geopack_2008: set to use the 2008 version of the Geopack library.
Must have version 9.2 of the IDL Geopack DLM installed to use
the geopack_2008 keyword
Returns: 1 on success 0 on failure
Example:
if(igp_test() eq 0) then return
Notes:
Should be called in all idl geopack wrapper routines
$LastChangedBy: jimm $
$LastChangedDate: 2015-01-26 14:30:54 -0800 (Mon, 26 Jan 2015) $
$LastChangedRevision: 16740 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_6_1/external/IDL_GEOPACK/igp_test.pro $
(See external/IDL_GEOPACK/igp_test.pro)
PROCEDURE: tcalc_pdyn
PURPOSE: This procedure calculates the solar wind dynamic pressure from proton speed and proton density, accounting for contributions from both
protons and alpha particles. Previous SPEDAS code only accounted for protons. OMNIweb provides a "Pressure" data set that assumes
f_alpha = N_a/N_p = 0.05, which according to Vassilis may be a little high. This routine accepts an f_alpha parameter, whicb defaults to 0.04.
INPUTS:
N_p_tvar: tplot variable name storing the solar wind
ion density(rho) cm^-3
V_p_tvar: tplot variable name storing the proton velocity
model: a string, should be 'TA15N' or 'TA15B'
Returns:
Dynamic pressure in units of nPa, suitable for passing to GEOPACK field models
KEYWORDS:
newname(optional): the name of the output tplot variable, defaults to 'Pdyn' if not provided.
times(optional): Timestamps at which the pressure shall be calculated. If not provided, the times of the density input variable will be used.
speed(optional): set this if Vp_tvar is stored as a speed
Notes:
Derivation of Alpha particle pressure correction is here: https://omniweb.gsfc.nasa.gov/ftpbrowser/bow_derivation.html
$LastChangedBy: jwl $
$LastChangedDate: 2021-07-28 18:16:15 -0700 (Wed, 28 Jul 2021) $
$LastChangedRevision: 30156 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_6_1/external/IDL_GEOPACK/tcalc_pdyn.pro $
(See external/IDL_GEOPACK/tcalc_pdyn.pro)
Procedure : tsy_valid_coords
Purpose:
Helper function used by Tsyganenko wrapper routines - checks coordinate system in dlimits structure
Input:
dlimits: dlimits structure from the tplot position variable
Keywords:
geopack_2008: specify to use the 2008 version of Geopack library. Must have v9.2 or later of the IDL Geopack DLM
Output:
Returns -1 on failure, +1 on success
$LastChangedBy: egrimes $
$LastChangedDate: 2015-03-17 12:53:14 -0700 (Tue, 17 Mar 2015) $
$LastChangedRevision: 17145 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_6_1/external/IDL_GEOPACK/tsy_valid_coords.pro $
(See external/IDL_GEOPACK/tsy_valid_coords.pro)
Procedure : tsy_valid_param
Purpose:
Helper function used by Tsyganenko wrapper routines. Validates model input
parameters and interpolates parameters onto position data
Input:
in_val: tplot variable containing parameter data to be interpolated onto
the position data
pos_name: the name of the position tplot variable
Returns -1L on failure
$LastChangedBy: jwl $
$LastChangedDate: 2021-09-20 11:08:14 -0700 (Mon, 20 Sep 2021) $
$LastChangedRevision: 30306 $
$URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/tags/spedas_6_1/external/IDL_GEOPACK/tsy_valid_param.pro $
(See external/IDL_GEOPACK/tsy_valid_param.pro)