Numerical Quadrature — Trapezoidal, Simpson, Gaussian

Numerical Analysis Source: Newton, Cotes, Gauss Cite
Primary: Newton, Cotes, Simpson
Publication: Numerical quadrature
Year: 18th c.
URL: Wikipedia

Approximate ∫f by weighted sum Σwⱼf(xⱼ). Degree of precision. Trapezoidal O(h²), Simpson O(h⁴), Gaussian quadrature exact for polynomials of degree 2n−1.

graph TD D1["Def: Quadrature rule\n∫f ≈ Σ wⱼf(xⱼ)"] D2["Def: Degree of precision\nexact for poly deg ≤ d"] D3["Def: Composite rule\nsubdivide [a,b]"] T1["Thm: Trapezoidal\nE = −(b−a)³f''(ξ)/12"] T2["Thm: Simpson\nE = −(b−a)⁵f⁽⁴⁾(ξ)/2880"] T3["Thm: Gaussian\nn nodes ⇒ degree 2n−1"] T4["Thm: Nodes = roots of\nLegendre Pₙ"] T5["Thm: Error composite\nO(hᵖ) with p=2,4,2n"] L1["Lemma: Peano kernel"] D1 --> D2 D1 --> D3 D2 --> T1 D2 --> T2 D2 --> T3 T3 --> T4 T1 --> T5 T2 --> T5 T3 --> T5 L1 --> T1 classDef definition fill:#b197fc,color:#fff classDef theorem fill:#51cf66,color:#fff classDef lemma fill:#74c0fc,color:#fff class D1,D2,D3 definition class T1,T2,T3,T4,T5 theorem class L1 lemma

Process Statistics

  • Nodes: 15
  • Edges: 12
  • Definitions: 3
  • Theorems: 5
  • Lemmas: 1
Frontier: Adaptive quadrature, quasi-Monte Carlo, cubature. math.NA