digama.m calculates DIGAMMA ( X ) = d ( LOG ( GAMMA ( X ) ) ) / dX psi_values.m returns some values of the Psi or Digamma function for testing. timestamp.m prints out the current YMDHMS date as a timestamp. asa103_test.m, a sample calling pr

由所获得的测井数据求取相应的层速度，密度，反射系数，并成图-convert the log data to layer velocity，decity，reflectance，and plot them