I want make a (t,h)graph. But I can 't solve a problem ㅜㅜ.

%% Time it takes for the cylinder to drain.

clear

f=@(H) 1/sqrt(H);

a=0.0001;

b=10:0.1:20;

n=16;

h=(b-a)./n;

so=0;

se=0;

for k=1:1:n-1

x1=a+k*h;

y=1/sqrt(x1);

if rem(k,2)==1

so=so+y1;%sum of odd terms

else

se=se+y1; %sum of even terms

end

end

Ans=h./3*(f(a)+f(b)+4*so+2*se);

d=0.1; D=1;

t =(D/d)^2 * (1/(2*9.81)^1/2)*Ans;

plot(b,t ), grid on

please check my script!

Answer 1

[Dyuman Joshi]

- y1 is not defined in the code

- If you want to perform vector operation using function handle, use element wise operations

f=@(H) 1./sqrt(H);
       %^
a=0.0001;
b=10:0.1:20;
n=16;
h=(b-a)./n;
so=0;
se=0;
for k=1:n-1
    x1=a+k*h;
    y=1/sqrt(x1); %check the formula
    if rem(k,2)==1
       so=so+y1;%sum of odd terms
    else
       se=se+y1; %sum of even terms
    end
end
val=h./(3*(f(a)+f(b)+4*so+2*se));
d=0.1; D=1;
t =(D/d)^2*(1/(2*9.81)^1/2)*val;
plot(b,t)
grid on