numdiff4.m

求解predator-prey的代码

%  numdiff4.m
% Matlab file for Part 4 of the Numerical Solutions
% of Differential Equations module

disp('********************************************')
disp('Part 4:  Another Initial Value Problem ')
disp('********************************************')
disp('  ')    

    format short

    disp('Edit your dfun.m file for the new DE: ')
    disp(' ')
    disp('  dy/dt = sin(y)  ')
    disp(' ')
    disp('Then, copy, paste, and edit MATLAB commands ')
    disp('from Part 3 to here to carry out the ')
    disp('calculations for Part 4. ')
    disp('  (You may have to adjust horizontal')
    disp('   and vertical scales to see what you')
    disp('   need to see.) ')
    disp(' ')
    disp('-----------------------------------------')
    disp('Answer all questions in part 4 as MATLAB')
    disp('comments in your diary file.') 
    disp(' ')
    disp(' ')
    disp('When you have finished part 4, to go on')
    disp('to part 5 of this module, type: numdiff5')
    disp(' ')