#x (kpc)   v (km/s)  v_err (km/s)
 -3.99   56.10    7.78
 -2.35   45.98    9.29
 -1.75   40.34    7.78
 -1.14   32.07    7.78
 -0.53    8.79    7.78
  0.08  -10.23    7.78
  0.69  -14.98    7.78
  1.29  -27.68    7.78
  1.90  -30.94    7.78
  2.51  -38.26    7.78
  3.12  -45.72    7.78
  3.73  -52.04    7.78
  4.33  -56.86    7.78
  4.94  -53.73    7.78
  5.55  -59.66    7.78
  6.16  -65.55    7.78
  6.77  -67.73    7.78
  7.64  -67.08    8.08