gauss.m

来自「关于数值计算的matlab程序代码,包含了很多的实用的算法.程序全部可以直接用的」· M 代码 · 共 23 行

function quad=gauss(f,a,b,A,W)

%Input   - f is the integrand input as a string 'f'
%        - a and b upper and lower limits of integration
%        - A is the 1 x N vector of abscissas from Table 7.9
%        - W is the 1 x N vector of weights from Table 7.9
%Output  - quad is the quadrature value

%  NUMERICAL METHODS: Matlab Programs
% (c) 2004 by John H. Mathews and Kurtis D. Fink
%  Complementary Software to accompany the textbook:
%  NUMERICAL METHODS: Using Matlab, Fourth Edition
%  ISBN: 0-13-065248-2
%  Prentice-Hall Pub. Inc.
%  One Lake Street
%  Upper Saddle River, NJ 07458

N=length(A);
T=zeros(1,N);
T=((a+b)/2)+((b-a)/2)*A;
quad=((b-a)/2)*sum(W.*feval(f,T));