PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/12/21-07:57:20
G02     203.1          38.1                4.1 +/-    0.66       6.1 +/-    0.66  0.060 / 0.120
G06     170.3          67.1                3.3 +/-    0.39       3.6 +/-    0.39  0.080 / 0.130
G12     308.3          15.3                1.1 +/-    3.11       2.7 +/-    3.11  0.080 / 0.180
G17     38.5           47.3                2.5 +/-    1.71       3.3 +/-    1.71  0.120 / 0.250
G19     8.0            63.5                2.3 +/-    0.48       2.6 +/-    0.48  0.040 / 0.040
G24     297.3          38.1                2.3 +/-    1.81       3.4 +/-    1.81  0.050 / 0.040
G28     104.8          29.3                5.1 +/-    0.90       9.1 +/-    0.90  0.020 / 0.020