PRN     Azimuth(d)     Elevation(d)   Vertical-TEC(tecu)    Slant-TEC(tecu)       S4(L1/L2)    2017/07/21-20:28:00
G02     308.0          80.0               11.2 +/-    0.77      11.3 +/-    0.77  0.030 / 0.020
G05     167.8          29.6               13.6 +/-    1.67      24.0 +/-    1.67  0.030 / 0.020
G06     41.6           41.4                9.5 +/-    0.92      13.5 +/-    0.92  0.100 / 0.130
G12     313.1          71.2                9.5 +/-    0.53      10.0 +/-    0.53  0.090 / 0.150
G17     86.2           10.0                9.5 +/-    1.83      26.3 +/-    1.83  0.200 / 0.330
G19     75.0           26.5                9.7 +/-    1.73      18.4 +/-    1.73  0.250 / 0.270
G24     231.3          24.6               12.6 +/-    2.01      24.9 +/-    2.01  0.030 / 0.030
G25     317.1          31.7                8.8 +/-    1.67      14.8 +/-    1.67  0.030 / 0.030