how do i find the min value using for loop?

clc

clear all

syms x

for yr = linspace(0,1,10)

f = sin(x);

fL = [0 pi];

iL = [0 pi];

Volume = pi*int((f-yr)^2,iL(1),iL(2));

s=double(Volume)

end

h=min(s)

Answer 1

[Chunru]

syms x 
smin = inf;     % initialize smin
for yr = linspace(0,1,10) 
    f = sin(x); 
    fL = [0 pi]; 
    iL = [0 pi]; 
    Volume = pi*int((f-yr)^2,iL(1),iL(2));
    s=double(Volume);
    if s<smin, 
        smin = s;
    end
end
%h=min(s)
smin

smin = 0.9437

[lakshmi sampath reddy Pulagum]

I could not understand it why have you choosen infinity as smin? Can you please explain?

[Chunru]

You put a very large value as the initial value to ensure that the min is from the data. You can go through a simple example of s = -10, -100, 200, 1000 and examine what happens with:

smin = inf
for  s = [-10, -100, 200, 1000] 
    if s<smin, 
        smin = s;
    end
end

[lakshmi sampath reddy Pulagum]

thank you so much.now i could understand it.its a good logic.once again thank you.

[lakshmi sampath reddy Pulagum]

and how can i find the point at which it is minimum

[lakshmi sampath reddy Pulagum]

clc

clear all

syms x

smin = inf; % initialize smin

for yr = linspace(0,1,10)

f = sin(x);

fL = [0 pi];

iL = [0 pi];

Volume = pi*int((f-yr)^2,iL(1),iL(2));

s=double(Volume);

if s<smin,

smin = s;

end

end

smin

for yr = linspace(0,1,10)

f = sin(x);

fL = [0 pi];

iL = [0 pi];

Volume = pi*int((f-yr)^2,iL(1),iL(2));

h=double(Volume)

if smin==h for yr= linspace(0,1,10);

disp(yr)

end

end

end

[lakshmi sampath reddy Pulagum]

i have tried this one but this doesnt make any sense can you help

[Chunru]

syms x 
smin = inf;     % initialize smin
locmin = nan;
for yr = linspace(0,1,10) 
    f = sin(x); 
    fL = [0 pi]; 
    iL = [0 pi]; 
    Volume = pi*int((f-yr)^2,iL(1),iL(2));
    s=double(Volume);
    if s<smin, 
        smin = s;
        locmin = yr;
    end
end
smin, yr

smin = 0.9437

yr = 1

[lakshmi sampath reddy Pulagum]

ahh it is wrong.its taking yr=1 for max and min too.can you please check it.

Answer 2

[lakshmi sampath reddy Pulagum]

thank you soo much.