How to show the iterations and the answers and the graph

clc

clear

m = 68.1;

g = 9.81;

t = 10;

v = 40;

f =@(c) (g*m*(1-(exp((-c*t)/m)))/c)-v;

N = 100; %iterations

err = 0.1;

c = 0.1:0.1:50;

x1 = c(1);

xu = c(end);

%root check

S = f(x1)*f(xu);

if S > 0

error('No root');

else

for i = 1:N

xr = xu - (f(xu)*(x1-xu))/(f(x1)-f(xu));

S = f(xr)*f(xu);

if S < 0

x1 = xr;

xr = xu - (f(xu)*(x1-xu))/(f(x1)-f(xu));

Err = abs(xr - x1);

if Err < err

break;

end

else if S > 0

xu = xr;

xr = xu - (f(xu)*(x1-xu))/(f(x1)-f(xu));

Err = abs(xr - xu);

if Err < err

break;

end

else

break;

end

ii = i;

end

end

end

disp(['The Root is: ' num2str(xr) ',with accuracy: ' num2str(Err) ', NO Iteration:' num2str(ii)]);

this is my finished code and how do i display the loop of this function? and also the display of the graph

Answer 1

[David Hill]

Why not use a while loop?

m = 68.1;
g = 9.81;
t = 10;
v = 40;
f =@(c) (g*m*(1-(exp((-c*t)/m)))/c)-v;
err = 1e-10;
c = 0.1:0.1:50;
x1 = c(1);
xu = c(end);
%root check
S = f(x1)*f(xu);
if S > 0
    error('No root');
else
Err=1;
count=1;
while Err>err 
    xr(count) = xu - (f(xu)*(x1-xu))/(f(x1)-f(xu));
    S = f(xr(count))*f(xu);
    if S < 0
        Err = abs(xr(count) - x1);
        x1 = xr(count);
    else
        Err = abs(xr(count) - xu);
        xu = xr(count);
    end
    count=count+1;
end
disp(['The Root is: ' num2str(xr(count-1)) ',with accuracy: ' num2str(Err)...
    ', NO Iteration:' num2str(count-1)]);
plot(1:count-1,xr)%this plots iterations vs. xr
end