How can we fit hyperbola to data?
59 views (last 30 days)
Show older comments
ishita agrawal
on 10 Sep 2017
Commented: Star Strider
on 30 Sep 2022
Hi, I have x and y coordinates for my data points. The data is fitted well with exponential fitting. However, I have to fit a hyperbola (a must condition for my results). I am using code,
% fit data k=0.002; % hit and trial
x = 1/xdata; y = k*1/x; p=plot(x,y)
I have attached excel file of my data. Accept my thanks in advance.
0 Comments
Accepted Answer
Star Strider
on 10 Sep 2017
Try this:
D = xlsread('data for hyperbola fitting.csv');
D = sortrows(D,1);
x = D(:,1);
y = D(:,2);
hyprb = @(b,x) b(1) + b(2)./(x + b(3)); % Generalised Hyperbola
NRCF = @(b) norm(y - hyprb(b,x)); % Residual Norm Cost Function
B0 = [1; 1; 1];
B = fminsearch(NRCF, B0); % Estimate Parameters
figure(1)
plot(x, y, 'pg')
hold on
plot(x, hyprb(B,x), '-r')
hold off
grid
text(0.7, 0.52, sprintf('y = %.4f %+.4f/(x %+.4f)', B))
‘Accept my thanks in advance.’
The sincerest expression of appreciation here on MATLAB Answers is to Accept the Answer that most closely solves your problem.
7 Comments
Rik
on 13 Mar 2021
Have you read the Wikipedia article about the R2? It is actually fairly easy to write code that calculates it.
Star Strider
on 30 Sep 2022
D = readmatrix('https://www.mathworks.com/matlabcentral/answers/uploaded_files/87569/data%20for%20hyperbola%20fitting.csv');
D = sortrows(D,1);
x = D(:,1);
y = D(:,2);
hyprb = @(b,x) b(1) + b(2)./(x + b(3)); % Generalised Hyperbola
B0 = [1; 1; 1];
mdl = fitnlm(x, y, hyprb, B0)
B = mdl.Coefficients.Estimate;
figure(1)
plot(x, y, 'pg')
hold on
plot(x, hyprb(B,x), '-r')
hold off
grid
xlabel('x')
ylabel('y')
text(0.7, 0.52, sprintf('$y = %.4f + \\frac{%.4f}{x %+.4f}$', B), 'Interpreter','latex', 'FontSize',12)
.
More Answers (0)
See Also
Categories
Find more on Classification in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!