User manual MATLAB CURVE FITTING TOOLBOX 2

[. . . ] Curve Fitting ToolboxTM 2 User's Guide How to Contact The MathWorks Web Newsgroup www. mathworks. com/contact_TS. html Technical Support www. mathworks. com comp. soft-sys. matlab suggest@mathworks. com bugs@mathworks. com doc@mathworks. com service@mathworks. com info@mathworks. com Product enhancement suggestions Bug reports Documentation error reports Order status, license renewals, passcodes Sales, pricing, and general information 508-647-7000 (Phone) 508-647-7001 (Fax) The MathWorks, Inc. 3 Apple Hill Drive Natick, MA 01760-2098 For contact information about worldwide offices, see the MathWorks Web site. Curve Fitting ToolboxTM User's Guide © COPYRIGHT 2001­2010 by The MathWorks, Inc. The software described in this document is furnished under a license agreement. The software may be used or copied only under the terms of the license agreement. [. . . ] You can view plots simultaneously and you can examine the goodness-of-fit statistics to compare your fits. This section describes how to compare multiple fits. Displaying Multiple Fits Simultaneously To compare plots and see multiple fits simultaneously, use the layout controls at the top right of the Surface Fitting Tool. Alternatively, you can click Window on the menu bar to select the number and position of tiles you want to display. The following example shows two fit tabs displayed side by side. You can see three fits in the session listed in the Table of Fits. 3-38 Comparing Surface Fits You can close fit tab displays (with the Close button, Fit menu, or context menu), but they remain in your session. The Table of Fits displays all your fits (open and closed). Double-click a fit in the Table of Fits to open a fit tab display. To remove a fit, see "Deleting a Surface Fit" on page 3-37 You can dock and undock individual fits and navigate between them using the standard MATLAB Desktop and Window menus in the Surface Fitting 3-39 3 Interactive Surface Fitting Tool. For more information, see "Opening and Arranging Desktop Tools" in the MATLAB Desktop Tools and Development Environment documentation. Displaying Surface, Residual, and Contour Plots Within each fit tab, you can display up to three plots simultaneously to examine the fit. Use the toolbar or View menu to select the type of plot to display: surface plot, residuals plot, or contour plot. See also "Exploring and Customizing Plots" on page 3-8. Surface Plot The surface plot displays by default. For polynomial and custom fits, you also can use the Tools menu to display Surface Prediction Bounds. When you display Surface Prediction Bounds, two additional surfaces are plotted to show the prediction bounds on both sides of your model fit. Choose which bounds to display: None, 90%, 95%, 99%, or Custom. The custom option opens a dialog box where you can enter the required confidence level. 3-40 Comparing Surface Fits The following example shows prediction bounds. The top and bottom surfaces show the prediction bounds at the specified confidence level on either side of your model fit surface. You can also switch your surface plot to a 2-D plot if desired. Your plot cursor must be in rotation mode. Select Tools > Rotate 3D if necessary. Then, right-click the plot to select X-Y, X-Z, or Y-Z view, or to select Rotate Options. All these context menu options are standard MATLAB 3­D plot tools. See "Rotate 3D -- Interactive Rotation of 3-D Views" in the MATLAB Graphics documentation. Residuals Plot On the Residuals Plot, you can view the errors between your fitted surface and your data, and you can remove outliers. See "Removing Outliers" on page 3-7. [. . . ] f = fittype('a*x^2+b*exp(n*x)'); category(f) ans = custom type(f) ans = customnonlinear g = fittype('fourier4'); category(g) ans = library type(g) ans = fourier4 See Also fittype, category, cflibhelp 7-91 type 7-92 A Bibliography [1] Barber, C. "The Quickhull Algorithm for Convex Hulls. " ACM Transactions on Mathematical Software. Data Reduction and Error Analysis for the Physical Sciences. "A Subspace, Interior, and Conjugate Gradient Method for Large-Scale Bound-Constrained Minimization Problems. " SIAM Journal on Scientific Computing. [. . . ]