Backward differentiation formula - Wikipedia
https://en.wikipedia.org/wiki/Backward_differentiation_formulaThe backward differentiation formula (BDF) is a family of implicit methods for the numerical integration of ordinary differential equations. They are linear multistep methods that, for a given function and time, approximate the derivative of that function using information from already computed time points, thereby increasing the accuracy of the approximation. These methods are especially used for the solution of stiff differential equations. The methods were first introduced …
Numerical differentiation - Wikipedia
https://en.wikipedia.org/wiki/Numerical_differentiationThe simplest method is to use finite difference approximations. A simple two-point estimation is to compute the slope of a nearby secant line through the points (x, f(x)) and (x + h, f(x + h)). Choosing a small number h, h represents a small change in x, and it can be either positive or negative. The slope of this line is This expression is Newton's difference quotient (also known as a first-order divided difference).
5 Numerical Differentiation
www2.math.umd.edu › ~dlevy › classesThe numerical differentiation formula, (5.9), then becomes f0(x k) = Xn j=0 f(x j)l0 j (x k)+ 1 (n+1)! f(n+1)(ξ x k) Y j=0 j6= k (x k −x j). (5.10) We refer to the formula (5.10) as a differentiation by interpolation algorithm. Example 5.1 We demonstrate how to use the differentiation by integration formula (5.10) in the case where n = 1 and k = 0.