centered intway 4points
centered intway 8points
centered intway 16points
centered intway 32points
centered intway accuracy=8
centered intway accuracy=16
centered intway accuracy=32
centered intway accuracy=64
forward intway accuracy=8
forward intway accuracy=16
forward intway accuracy=32
forward intway accuracy=64
Bengt Fornberg, Generation of Finite Difference Formulas of Arbitrarily Spaced Grids
Mathematics of Computaion, vol.51, no.184, (1988)