Cant get the equation to work

clc

num_values=11;    
first_val=0;
time=zeros(1,num_values);
z(1)=first_val;
s=zeros(1,11);
time(1)=first_val;
t=sym('t');

TU(1)=5*pi/180;
TU(2)=7*pi/180;
TU(3)=6*pi/180;
TU(4)=9*pi/180;
TU(5)=12*pi/180;
TU(6)=17*pi/180;
TU(7)=19*pi/180;
TU(8)=27*pi/180;
TU(9)=33*pi/180;
TU(10)=36*pi/180;
TU(11)=45*pi/180;

for n=2:11
    time(n)=(n-1)*15;
    z(n)=(-z(n-1)+((2*(TU(n)-TU(n-1)))/(time(n)-time(n-1))));
    sprintf('z= %.05f \n',z)
end
for n=2:10;
    s(n)=((z(n)-z(n-1))/(2*(time(n)-time(n-1)))) * ((t-time(n-1)).^2) + z(n-1)*(t-time(n-1))+TU(n-1);

end

Im trying to get the values from the equation with s using the values of the equation with z and i dont know how. In the workspaces it says that s is a 1x11 matrix but i think it should be 1x10

[KSSV]

You have initiated s as zeros(1,11);....so according to your code..it is correct.

[KSSV]

YOu can replace the array TU with the following:

TU = [5 7 6 9 12 17 19 27 33 36 45]*pi/180;

[Clara Ghattas]

even then, it says that the left and right sides have different number if elements so it cant work

[Jan]

"it says" - who is it? Please post the complete error message, such that the readers do not have to guess, which line fails with which message.

Answer 1

[Areej Varamban Kallan]

Hi Clara,

I have executed your code and the error message I get is "Unable to convert expression into double array". The variable 's' is defined to be a double matrix and the variable 't' is defined to be a symbolic variable. In the second for loop you are doing certain computations using the symbolic variable 't'. The results of such computations will be of symbolic type. As a result your code is attempting to assign a symbolic value to a double matrix. This is not valid.

Please redine s as:

s=sym(zeros(1,11));