PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2018/02/21-21:27:50
G07     308.9          47.2                9.2 +/-    0.97      12.0 +/-    0.97  0.150 / 0.200
G08     128.8          41.8               12.5 +/-    1.11      17.7 +/-    1.11  0.520 / 0.520
G09     297.9          79.3                7.8 +/-    0.31       7.9 +/-    0.31  0.050 / 0.050
G16     42.2           23.0                7.7 +/-    1.53      15.7 +/-    1.53  0.040 / 0.050
G23     145.4          59.8               11.0 +/-    0.41      12.6 +/-    0.41  0.150 / 0.220
G27     75.5           36.9               11.0 +/-    1.12      16.9 +/-    1.12  0.140 / 0.230
G28     225.3          15.0               11.9 +/-    2.79      29.6 +/-    2.79  0.050 / 0.060
G30     289.3          26.7                9.3 +/-    1.51      17.5 +/-    1.51  0.040 / 0.060