MATLAB: Contour Plotting in Surface Fitting Tool

contourfitting toolMATLAB

Hi All,

I used the surface fitting tool to generate a contour plot on some scattered data (vector x, vector y, and vector z). I would like to know if there are any ways to plot only the specified contour levels and also label those contour levels just like the contour function.

Please let me know if there are any alternatives to do contour plotting using scattered data. I have tried the TriScatteredInterp method, but the contour plot did not make any sense.

Any help will be greatly appreciated!

Thanks,

Lynniz

Best Answer

If I understand your question correctly, this can be achieved by exporting the data and creating a new contour plot that can be modified. Supporting information:

http://www.mathworks.com/support/solutions/en/data/1-AMH9HS/index.html

Related Solutions

MATLAB: How to create a contour for a fittype object

One simple way is to get the data from the surface that the plot method creates.

h = plot(fitresult, [full_data(:,1), full_data(:,2)], full_data(:,3) );
s = findobj(h,'Type','surface');
figure
contour(s.XData,s.YData,s.ZData)

The "cleaner" option would be to use the feval method. You need to pass in the XData and YData. Something like this:

load franke
T = table(x,y,z);
f = fit([T.x, T.y],T.z,'linearinterp');
[x,y]=meshgrid(linspace(500,3500,40),linspace(0,1,40));
z=feval(f,x,y);
contour(x,y,z)

MATLAB: How to display the contour line values from a contour plot generated using the curve fitting tools

If, in the auto-generated code from the gui you specify h (the handler to the plots) as an aditional output variable you can access those data.

    function [fitresult, gof, h] = createFit(x, y, z)
    %CREATEFIT(X,Y,Z)
    %  Create a fit.
    %


    %  Data for 'untitled fit 1' fit:
    %      X Input : x
    %      Y Input : y
    %      Z Output: z
    %  Output:
    %      fitresult : a fit object representing the fit.
    %      gof : structure with goodness-of fit info.
    %
    %  See also FIT, CFIT, SFIT.
    %  Auto-generated by MATLAB on 28-Apr-2017 12:52:15
    %%Fit: 'untitled fit 1'.
    [xData, yData, zData] = prepareSurfaceData( x, y, z );
    % Set up fittype and options.
    ft = fittype( 'lowess' );
    % Fit model to data.
    [fitresult, gof] = fit( [xData, yData], zData, ft, 'Normalize', 'on' );
    % Make contour plot.
    figure( 'Name', 'untitled fit 1' );
    h = plot( fitresult, [xData, yData], zData, 'Style', 'Contour' );
    legend( h, 'untitled fit 1', 'z vs. x, y', 'Location', 'NorthEast' );
    % Label axes
    xlabel x
    ylabel y
    grid on

h is an array and you have to guess which component is the one for the contour plot. In my example it was h(1). That component is the same as in [C, h] = contour(...), and you can use it in the same way. h(1).ContourMatrix has the matrix C that contour would output, and, in particular you can write

clabel(h(1).ContourMatrix, h(1))

to have the contour lines of your plot labelled.

Best Answer

Related Solutions

MATLAB: How to create a contour for a fittype object

MATLAB: How to display the contour line values from a contour plot generated using the curve fitting tools

Related Question