PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2019/09/21-16:27:50
G02     54.6           36.8                7.8 +/-    0.92      12.0 +/-    0.92  0.150 / 0.320
G05     69.2           66.9                7.9 +/-    0.47       8.5 +/-    0.47  0.170 / 0.310
G12     184.2          37.4                9.2 +/-    1.42      14.0 +/-    1.42  0.300 / 0.490
G13     130.4          11.7               12.5 +/-    3.79      33.6 +/-    3.79  0.440 / 0.520
G21     267.6          13.5                6.0 +/-    9.28      15.4 +/-    9.28  0.030 / 0.040
G25     246.0          55.0                8.2 +/-    0.76       9.7 +/-    0.76  0.030 / 0.030
G29     325.0          49.4                6.6 +/-    0.64       8.4 +/-    0.64  0.050 / 0.060