Direct surface wave radial anisotropy tomography package

Direct surface wave radial anisotropy tomography package (DSurfRTomo)

modified from
        DSurfTomo (https://github.com/HongjianFang/DSurfTomo)

    see the following references for details

    Fang, H., Yao, H., Zhang, H., Huang, Y. C., & van der Hilst, R. D. (2015). Direct inversion of surface wave dispersion for three-dimensional shallow crustal structure based on ray tracing: methodology and application. Geophysical Journal International, 201(3), 1251-1263.

    and    

    Rawlinson, N. & Sambridge, M., 2004. Wave front evolution in strongly heterogeneous layered media using the fast marching method, Geophys. J. Int., 156(3), 631–647

please refer to:

        Hu, S., H. Yao, and H. Huang (2019), Direct surface wave radial
        anisotropy tomography in the crust of the eastern Himalayan
        syntaxis. Submitted

for details of this code

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The dispersion data (ALLR.dat for Rayleigh wave
and ALLT.dat for Love wave), resulting model (DSurfRTomo.inMeasurement.dat)
in the crust of the eastern Himalayan syntaxis is provided in example/

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output is
    : lon lat dep vsv gamma

For visualization,
to compute average shear wave velocity (vs) and radial anisotropy (xi)
using the following equaitons:

1.    vs=vsv*(1+gamma)/2.0              xi=2*(gamma-1)/(gamma)*100
or
2.    vs=vsv*sqrt((2+gamma^2)/3)        xi=gamma^2