i am getting error in the plot function it says array indices must be +ve int or logical value

v1(1)=2;
v2(1)=4;
v3(1)=-1;
for n = 1:50
    a1(n)=v1(n)-v2(n);
    v1(n+1)=v1(n)+a1(n)*0.1;
    a2(n)=v3(n)-3;
    v2(n+1)=v2(n)+a2(n)*0.1;
    a3(n)=a1(n)-a2(n);
    v3(n+1)=v3(n)+a3(n)*0.1;
end

t= 0:0.1:5;

plot(t,v1(t*10+1))
hold all
plot(t,v2(t*10+1))
plot(t,v3(t*10+1))

[KSSV]

Why you want tp index v with t? you need not to do it while plotting.

The error is due to indexing. Array indices should be posititive integers in MATLAB. If you use ractions, you will get error.

A = rand(1,3) ;
A(0.5)  % error

Array indices must be positive integers or logical values.

Answer 1

[KSSV]

t= 0:0.1:5;
nt = length(t) ; 
v1 = zeros(size(t)) ;
v2 = zeros(size(t)) ;
v3 = zeros(size(t)) ; 
v1(1)=2;
v2(1)=4;
v3(1)=-1;
for n = 1:50
    a1=v1(n)-v2(n);
    v1(n+1)=v1(n)+a1*0.1;
    a2=v3(n)-3;
    v2(n+1)=v2(n)+a2*0.1;
    a3=a1-a2;
    v3(n+1)=v3(n)+a3*0.1;
end

plot(t,v1)  
hold all
plot(t,v2)
plot(t,v3)

[Shraman]

ah thanks very much

[KSSV]

Thanks is accepting/ voting the answer. :)