Matlab实现——Adams-Bashforth-Method

 abm.m

function A = abm(f,T,Y)%Input   - f is the function entered as a string 'f'%        - T is the vector of abscissas%        - Y is the vector of ordinates%Remark.   The first four coordinates of T and Y must %          have starting values obtained with RK4%Output  - A=[T?? Y??] where T is the vector of abscissas %          and Y is the vector of ordinatesn=length(T);if n>=5    F=zeros(1,4);    F=feval(f, T(1:4), Y(1:4));    h=T(2)-T(1);    for k=4:n-1         %Predictor         p=Y(k)+(h/24)*(F*[-9  37  -59  55]');         T(k+1)=T(1)+h*k;         F=[F(2) F(3) F(4) feval(f, T(k+1), p)];         %Corrector         Y(k+1)=Y(k)+(h/24)*(F*[1  -5  19  9]');         F(4)=feval(f, T(k+1), Y(k+1));    end    A=[T' Y'];end

fun1.m

function f=fun1(t,y)f=t.^2-y;

Untitlel.m

T=[0,0.05,0.10,0.15,0.20,0.25,0.03];Y=[1,0.95127058,0.90516258,0.86179202,0,0,0];f='fun1';A=abm(f,T,Y)