I am getting error like invalid expression

조회 수: 9(최근 30일)
nune pratyusha
nune pratyusha 2022년 8월 26일
댓글: nune pratyusha 2022년 8월 26일
function Le=lyapunovk(n,rhs_ext_fcn,tstart,stept,tend,ystart,R);
n1=n; n2=n1*(n1+1);
% Number of steps
nit = round((tend-tstart)/stept);
% Memory allocation
y=zeros(n2,1); cum=zeros(n1,1); y0=y;
gsc=cum; znorm=cum;
% Initial values
y(1:n)=ystart(:);
for i=1:n1
y((n1+1)*i)=1.0; end;
t=tstart;
% Main loop
for ITERLYAP=1:nit
% Solutuion of extended ODE system
[T,Y] = ode15s(rhs_ext_fcn,[t t+stept],y,R);
Y=transpose(Y);
t=t+stept;
y=Y(size(Y,1),:);
for i=1:n1
for j=1:n1
y0(n1*i+j)=y(n1*j+i); end;
end;
%
% construct new orthonormal basis by gram-schmidt
%
znorm(1)=0.0;
for j=1:n1
znorm(1)=znorm(1)+y0(n1*j+1)^2; end;
znorm(1)=sqrt(znorm(1));
for j=1:n1
y0(n1*j+1)=y0(n1*j+1)/znorm(1); end;
for j=2:n1
for k=1:(j-1)
gsc(k)=0.0;
for l=1:n1
gsc(k)=gsc(k)+y0(n1*l+j)*y0(n1*l+k); end;
end;
for k=1:n1
for l=1:(j-1)
y0(n1*k+j)=y0(n1*k+j)-gsc(l)*y0(n1*k+l);
end;
end;
znorm(j)=0.0;
for k=1:n1
znorm(j)=znorm(j)+y0(n1*k+j)^2; end;
znorm(j)=sqrt(znorm(j));
for k=1:n1
y0(n1*k+j)=y0(n1*k+j)/znorm(j); end;
end;
%
% update running vector magnitudes
%
for k=1:n1
cum(k)=cum(k)+log(znorm(k)); end;
%
% normalize exponent
%
for k=1:n1
lp(k)=cum(k)/(t-tstart);
end;
% Output modification
i=1;
while i<=n1
j=1;
while j<=n1;
y(n1*j+i)=y0(n1*i+j);
j=j+1;
end
i=i+1;
end;
y=transpose(y);
nit=nit+1;
end
function f=l_ext(t,x,R)
SIGMA = 10;
BETA = 8/3;
f=zeros(9,1);
X= [x(4) x(7) x(10);
x(5) x(8) x(11);
x(6) x(9) x(12)];
%Lorenz equation
f(1)=SIGMA*(x(2)-x(1));
f(2)=-x(1).*x(3)+R*x(1)-x(2);
f(3)=x(1).*x(2)-BETA*x(3);
%Linearized system
Jac=[-SIGMA, SIGMA, 0;
R-x(3), -1, -x(1);
X(2), x(1), -BETA];
%Variational equation
f(4:12)=Jac*X;
%Output data must be a column
function run_L_p(n,rhs_ext_fcn,0,0.5,200,[0 1 0],10,R_min,R_max,nk);
hold on;
rhs_ext_fcn=@l_ext
n=3;
nk=100;
R_min=10;
R_max=28;
R_step=(R_max-R_min)/nk
R=R_min;
while R<=R_max
lp=lyapunovk(3,@l_ext,0,0.5,200,[0 1 0],10,R);
R=R+R_step;
plot(R,lp);
end
I am gettion error:
Invalid expression. Check for missing multiplication operator, missing or unbalanced delimiters, or other syntax error. To construct matrices, use brackets instead of parentheses.

답변(1개)

Karim
Karim 2022년 8월 26일
the error is located in syntax of the run_L_p function. You need to change the numeric values into variables
i.e. change
function run_L_p(n,rhs_ext_fcn,0,0.5,200,[0 1 0],10,R_min,R_max,nk)
into
function run_L_p(n,rhs_ext_fcn,var1,var2,var3,var4,var5,R_min,R_max,nk)
before call the function you need to define the extra variables as
var1 = 0;
var2 = 0.5;
var3 = 200;
var4 = [0 1 0];
var5 = 10;
or if they are fixed you can set them in the function itself.
  댓글 수: 5
nune pratyusha
nune pratyusha 2022년 8월 26일
yes after modification i changed functiom name as run_L_p1 and saved it as run_L_p1

댓글을 달려면 로그인하십시오.

태그

제품


릴리스

R2021b

Community Treasure Hunt

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

Start Hunting!

Translated by