Name: SUPERPO_INTERPOL Purpose: This routine calculates the minimum (maximum, etc.) function of several time series. The time bin (resolution) can be specified. An example would be the calculation of AL (AU, AE) indices. The results are stored in tplot variables. This routine interpolates at desired sampling rate. An alternative routine exists which does not interpolate (see 'superpo_histo'). Variable: quantities = string of tplot variable names (e.g., ground stations) Keywords: res = sampling interval (by default 60 sec) min = e.g., 'thg_pseudoAL' max = e.g., 'thg_pseudoAU dif = e.g., 'thg_pseudoAE avg = average values med = median values Example: superpo_interpol,'thg_mag_ccnv_x thg_mag_drby_x thg_mag_fsim_x thg_mag_fsmi_x thg_mag_fykn_x', min='thg_pseudoAL',avg='thg_avg' res=600n.0, superpo_interpol,'thg_mag_????_x',min='thg_pseudoAL', res=30.0 superpo_interpol,'thg_mag_????_x' ; default values for all keywords Speed: With an input of magnetometer data from 27 ground stations (178000 data points each) and a bin resolution of 60 s (res=60.0), the running time is less than 1 sec (using IBM PC). With res=1.0, the running time is around 1 sec. Notes: Written by Andreas Keiling, 30 July 2007 $LastChangedBy: $ $LastChangedDate: $ $LastChangedRevision: $ $URL $