PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2018/02/21-21:27:40
G07     308.9          47.2               11.9 +/-    1.41      15.5 +/-    1.41  0.230 / 0.340
G08     128.8          41.8               13.8 +/-    1.03      19.5 +/-    1.03  0.240 / 0.290
G09     297.9          79.3               10.0 +/-    1.04      10.2 +/-    1.04  0.120 / 0.250
G16     42.2           23.0                8.5 +/-    0.52      17.4 +/-    0.52  0.130 / 0.260
G23     145.4          59.8               12.8 +/-    1.76      14.5 +/-    1.76  0.040 / 0.090
G27     75.5           36.9                9.5 +/-    0.90      14.6 +/-    0.90  0.050 / 0.080
G28     225.3          15.0               13.7 +/-    1.30      34.1 +/-    1.30  0.060 / 0.070
G30     289.3          26.7               11.6 +/-    1.44      21.8 +/-    1.44  0.060 / 0.080