Python implementation of MATLAB "intgrad1" function by John D'Errico.
Note: only the method 2 (integrated spline model) has been implemented.
John D'Errico (2024). Inverse (integrated) gradient (https://www.mathworks.com/matlabcentral/fileexchange/9734-inverse-integrated-gradient), MATLAB Central File Exchange. Retrieved September 10, 2024.