fractional-order,Index exceeds the number of array elements (1)

1 view (last 30 days)
Hi
Good time
I wrote this code but it gives an error
Please help me
thank you
%%
n=100;
u1=[0,0]';
X1=[-4,-2,0]';
a=0.9;
h=0.9;
cp1=1;cp2=1;cp3=1;
for j=1:n
c1(j)=(1-(1+a)/j)*cp1;
c2(j)=(1-(1+a)/j)*cp2;
c3(j)=(1-(1+a)/j)*cp3;
cp1=c1(j); cp2=c2(j); cp3=c3(j);
end
% initial conditions setting:
v1(1)=u1(1);
w1(1)=u1(2);
x1(1)=X1(1); y1(1)=X1(2); z1(1)=X1(3);
% calculation of phase portraits /numerical solution/:
for i=2:n
x1(i)=h*cos(z1(i-1))*v1(i-1) - memo(x1, c1, i);
y1(i)=h*sin(z1(i-1))*v1(i-1)-memo(y1, c2, i);
z1(i)=h*w1(i-1)-memo(z1, c3, i) ;
end
%%
function [yo] = memo(r, c, k)
%
temp = 0;
for j=1:k-1
temp = temp + c(j)*r(k-j);
end
yo = temp;
%
%%%%% error
Index exceeds the number of array elements (1).
Error in exocstrstateFcnCT1 (line 28)
x1(i)=h*cos(z1(i-1))*v1(i-1) - memo(x1, c1, i);

Answers (1)

Walter Roberson
Walter Roberson on 23 Dec 2020
You only initialize
v1(1)=u1(1);
and you do not assign to any other entry in v1, so when i becomes 3, v1(i-1) becomes v1(2) which does not exist.
  11 Comments
Farshid R
Farshid R on 23 Dec 2020
function z=myStateFunction1(x,u,X2G,X3G,k)
a=0.9;h=0.9;
cp1=1;cp2=1;cp3=1;
c1= nchoosek(a,k);
c2=nchoosek(a,k);
c3=nchoosek(a,k);
cp1=c1; cp2=c2; cp3=c3;
z(1)=x(1); z(2)=x(2); z(3)=x(3);
z(1)=h*cos(x(3))*u(1) - memo(z(1), c1, k);
z(2)=h*sin(x(3))*u(1)-memo(z(2), c2, k);
z(3)=h*u(2)-memo(z(3), c3, k) ;
%%
function [x0] = memo1(r, c, k)
temp = 0;
for j=1:k-1
temp = temp + c(j)*r(k-j);
end
x0 = temp;
Start of Error Report
------------------------------------------------------
Array indices must be positive integers or logical values.

Sign in to comment.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!