PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/07/29-21:57:50
G02     51.1           41.0                9.1 +/-    1.35      13.0 +/-    1.35  0.040 / 0.060
G05     80.7           69.7                9.2 +/-    0.36       9.8 +/-    0.36  0.040 / 0.060
G12     185.9          40.0               11.9 +/-    1.03      17.4 +/-    1.03  0.050 / 0.060
G20     203.0          52.8               10.5 +/-    0.99      12.8 +/-    0.99  0.030 / 0.050
G21     264.7          12.4               12.5 +/-    1.93      33.2 +/-    1.93  0.040 / 0.080
G25     240.7          56.4               11.7 +/-    0.65      13.7 +/-    0.65  0.050 / 0.060
G29     324.2          48.9                9.6 +/-    0.92      12.3 +/-    0.92  0.200 / 0.680