How to find the x value at the maximum?

5 views (last 30 days)
sophp
sophp on 7 Feb 2018
Edited: Jan on 7 Feb 2018
Here is a MATLAB code to find the maximum of the Y_B (which is a function of
T and t) against t.
t = 0.2:0.1:20;
T = 600:2:850;
for i = 1:numel(T)
k1 = 1e7 .* exp(-12700 ./ T(i));
k2 = 5e4 .* exp(-10800 ./ T(i));
k3 = 7e7 .* exp(-15000 ./ T(i));
for j = 1:numel(t)
Y_B(i,j) = (k1/(k2-k1-k3))*(exp(-(k1+k3)*t(j))-exp(-k2*t(j)));
end
end
plot(t, max(Y_B, [], 1));
How do I find the corresponding value of T at the Y_Bmax and plot it against t?
  1 Comment
Jan
Jan on 7 Feb 2018
Edited: Jan on 7 Feb 2018
As mentioned in your other thread, this is more efficient and nicer without a loop:
t = 0.2:0.1:20;
T = (600:50:850).';
k1 = 1e7 .* exp(-12700 ./ T);
k2 = 5e4 .* exp(-10800 ./ T);
k3 = 7e7 .* exp(-15000 ./ T);
Y_B = (k1 ./ (k2-k1-k3)) .* (exp(-(k1+k3) * t) - exp(-k2*t)); % >= R2016

Sign in to comment.

Accepted Answer

Birdman
Birdman on 7 Feb 2018
Edited: Birdman on 7 Feb 2018
t = 0.2:0.1:20;
T = 600:2:850;
for i = 1:numel(T)
k1 = 1e7 .* exp(-12700 ./ T(i));
k2 = 5e4 .* exp(-10800 ./ T(i));
k3 = 7e7 .* exp(-15000 ./ T(i));
for j = 1:numel(t)
Y_B(i,j) = (k1/(k2-k1-k3))*(exp(-(k1+k3)*t(j))-exp(-k2*t(j)));
end
end
[val,idx]=max(Y_B);
plot(T(idx), val,'-o');

More Answers (0)

Categories

Find more on Data Type Identification in Help Center and File Exchange

Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!