matlab ode45 error

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Saptarshi Bhattacharjee
评论： madhan ravi 2019-2-6
tspan= linspace(0,0.1,1);
yinit = [0.5 , 0.8];
[t,y] = ode45(@maths(t,y), tspan, yinit) --->error invalid expression,use parenteses,mismatched delimiters??
plot(t,y(:,1),'-o');
xlabel("x values");
ylabel("y values");
plot(t,y(:,2),'-.');
plot(t,y(:,1),'-o',t,y(:,2),'-.');
plot(y(:,1),y(:,2));
plot(y(:,2),y(:,1));

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madhan ravi
madhan ravi 2019-2-5
[t,y]=ode45(@maths,...)
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madhan ravi
madhan ravi 2019-2-6
Saptarshi Bhattacharjee's answer moved here:
After correcting the original code, I get different graphs with different number of points in linspace and different graphs with different values of yinit .So my doubt is : is this a limitation of ode45 or is it because ode45 is a numerical method?
madhan ravi
madhan ravi 2019-2-6
It's always a good idea to read the documentation changing the tspan with intermediate points may change the solution. So the best idea is to just define the start point and the end point and let the solver evaluate with it's default step size. yinit is the starting point where the solution begins (initial condition). Please refer https://www.mathworks.com/help/matlab/ref/ode45.html#bu00_4l_sep_shared-tspan which explains it clearly.

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