PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/07/20-19:42:40
G02     227.7660       66.3277         16.0448 +/-  1.2924   17.3506 +/-  1.2924  0.040 / 0.040
G06     43.2016        63.2177          4.4606 +/- 19.1358    4.9333 +/- 19.1358  0.040 / 0.040
G12     321.8152       48.3935         13.9022 +/-  0.8164   17.8908 +/-  0.8164  0.040 / 0.040
G17     68.3799        23.1630         15.0391 +/-  9.2132   30.6686 +/-  9.2132  0.040 / 0.050
G19     53.9057        40.1677         -5.5194 +/- 51.6870   -8.0059 +/- 51.6870  0.220 / 0.380
G25     315.9339       11.8748          5.5165 +/- 34.9595   14.7707 +/- 34.9595  0.260 / 0.310