Upward continuation of Grid data

Upward continuation is a process of determining the data on a surface above a surface on which the data is recorded or known. It utilizes the Green's identities. Here the Fourier domain utilization has been used to calculate the upward continuation of the Gravity and Magnetic data of Exploration Geophysics. The code returns the contour map of observed data as well the upward continued data, level being decided by the user input.