Procedure: tt89 Purpose: tplot wrapper for the functional interface to the IDL Geopack implementation of the Tsyganenko 89 and IGRF model. Input: pos_gsm_tvar: the tplot variable storing the position in gsm coordinates(can use standard globbing) Keywords: kp(optional): the requested value of the kp parameter(default: 2) can also be a tplot variable name if it is a tplot variable name the kp values stored in the variable will be interpolated to match the time grid of the position input values period(optional): the amount of time between recalculations of geodipole tilt in seconds(default: 600) increase this value to decrease run time get_nperiod(optional): Return the number of periods used in the time interval newname(optional):the name of the output variable. (default: pos_gsm_tvar+'_bt89') This option is ignored if globbing is used. error(optional): named variable in which to return the error state of this procedure call. 1 = success, 0 = failure igrf_only(optional): Set this keyword to turn off the t89 component of the model and return only the igrf component get_tilt(optional): Set this value to a tplot variable name in which the geodipole tilt for each period will be returned One sample will be returned for each period with time at the center of the period. set_tilt(optional): Set this to a tplot variable name or an array of values containing the dipole tilt that should be used. If a tplot input is used it will be interpolated to match the time inputs from the position var. Non-tplot array values must match the number of times in the tplot input for pos_gsm_tvar add_tilt(optional): Set this to a tplot variable name or an array of values containing the values to be added to the dipole tilt that should be used for each period. If a tplot input is used it will be interpolated to match the time inputs from the position var. Non-tplot array values must match the number of times in the tplot input for pos_gsm_tvar geopack_2008 (optional): Set this keyword to use the latest version (2008) of the Geopack library. Version 9.2 of the IDL Geopack DLM is required for this keyword to work. Output: Stores the result of the field model calculations in tplot variables Notes: 1. Converts from normal gsm to rgsm by dividing vectors by earth's radius(6374 km) ie inputs should be in km 2. Input must be in GSM coordinates 3. Haje Korth's IDL/Geopack DLM must be installed for this procedure to work $LastChangedBy: egrimes $ $LastChangedDate: 2014-03-18 09:51:27 -0700 (Tue, 18 Mar 2014) $ $LastChangedRevision: 14573 $ $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/external/IDL_GEOPACK/t89/tt89.pro $