pro mms_test_j2000 mms_load_state, probe='1', datatype='pos', trange=['2015-09-01', '2015-09-02'] get_data, 'mms1_defeph_pos', data=dj2000, dlimits=dlj2000, limits=lj2000 cotrans, 'mms1_defeph_pos', 'mms1_defeph_gei', /j20002gei cotrans, 'mms1_defeph_gei', 'mms1_defeph_j2000', /gei2j2000 get_data, 'mms1_defeph_pos', data=dj2000, dlimits=dlj2000, limits=lj2000 get_data, 'mms1_defeph_gei', data=dgei, dlimits=dlgei, limits=lgei get_data, 'mms1_defeph_j2000', data=dj20001, dlimits=dlj20001, limits=lj20001 tsgei=time_struct(dgei.x) tsj2000=time_struct(dj2000.x) tsj20001=time_struct(dj20001.x) ; create an integer array for ic_conv_matrix ; the format is YYYYDDD for [n,0] and sss (seconds of day) for [n,1] orbtime = make_array(n_elements(dgei.x), 2, /long) orbtime[*,0] = long((tsgei.year * 1000.) + tsgei.doy) orbtime[*,1] = long(fix(tsgei.sod)) data_ic = dj2000 for i=0,n_elements(dgei.x)-1 do begin ic_conv_matrix, reform(orbtime[i,*]), cmatrix data_ic.y[i,*] = reform(dj2000.y[i,*]) # (cmatrix) endfor j2000_mag = sqrt(total(dj2000.y^2,2)) gei_mag = sqrt(total(dgei.y^2,2)) j20001_mag = sqrt(total(dj20001.y^2,2)) print, 'Compare Radial distances - they should be close to zero' print, 'min/max j2000/j20001 ' mm = minmax(abs(j2000_mag-j20001_mag)) print, mm stop end