e953.m

matlab算法集 matlab算法集

%-------------------------------------------------------------------
% Example 9.5.3: Vibrating String
%-------------------------------------------------------------------

% Initialize 

   clc
   clear
   global c1 c2
   c1 = 0.1;        
   c2 = 0.1;  
   a = 2;            % string length
   m = 80;           % t precision 		
   n = 39;           % x precision 
   T = 1.0;          % maximum t  
   beta = 4.0;       % gain 
   E = 0;	     % error 	

% Find gamma 

   fprintf ('Example 9.5.3: Vibrating String\n'); 
   dt = T/m;
   dx = a/(n+1);
   gamma = beta*dt*dt/(dx*dx);
   show ('gamma',gamma);

% Solve wave equation 

   disp ('Solving wave equation ...');      
   [t,x,U] = wave1 (T,a,m,n,beta,'funf953','fung953');
   plotxyz (t,x,U,'Vibrating String','t','x','u');

% Check the accuracy 

   for i = 1 : m+1
      for j = 1 : n
      	 w(i,j) = funv953(t(i),x(j));
         E = max([E,abs(U(i,j)-w(i,j))]);
      end
   end
   show ('maximum error',E);
%-------------------------------------------------------------------