PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2018/12/21-14:27:40
G10     263.9          36.8                6.9 +/-    1.14      10.5 +/-    1.14  0.030 / 0.030
G13     43.3           20.2                4.1 +/-    1.19       9.1 +/-    1.19  0.030 / 0.040
G15     63.6           51.9                5.5 +/-    0.55       6.8 +/-    0.55  0.080 / 0.070
G20     292.1          59.0                5.7 +/-    0.95       6.5 +/-    0.95  0.090 / 0.080
G21     6.3            71.4                5.1 +/-    0.38       5.3 +/-    0.38  0.160 / 0.210
G24     119.0          12.9                9.5 +/-    1.68      25.0 +/-    1.68  0.160 / 0.280
G27     320.9          14.1                1.4 +/-    2.00       3.5 +/-    2.00  0.180 / 0.260
G29     166.3          32.8                9.1 +/-    1.40      15.0 +/-    1.40  0.170 / 0.230