You have a numerical method that provides approximations of a value, which may not be very accurate.
Use the chosen numerical method to compute the value of interest with multiple step sizes (e.g., h, h/2, h/4).
Apply the Richardson extrapolation formula, which combines the results from different step sizes to provide a more accurate estimate. The formula is typically expressed as:
R(h) = 2^n * F(h/2) - F(h) / (2^n - 1)
Where R(h) is the extrapolated result, F(h) is the result obtained with the original step size h, and n is the order of accuracy of the method.
You can assess the accuracy and convergence of the Richardson extrapolation by comparing the results obtained with different step sizes.
The result of the Richardson extrapolation, R(h), is a more accurate approximation of the desired value compared to the original numerical method.
Richardson extrapolation is a powerful technique for improving the accuracy of numerical approximations, particularly when dealing with methods of known order of accuracy.