CURVE FITTING TOOLBOX IN MATLAB

What is Curve Fitting Toolbox?

Curve Fitting Toolbox is a programme that allows you to fit curves and surfaces to data. You can use the toolbox to conduct exploratory data analysis, pre- and post-process data, compare candidate models, and eliminate outliers.

Some examples using curve Fitting Tool Box:-

Example 1:- Find the best “a1” and “a2” values that help the following equation to well fit the data reported in table below. what is the “ r² ”?

x   1     2      3      4       5        6       7         8       9  
y  8.5   12.5   15.8   17.9    19.1    22.3     23.6      26      27 

and given equation is

y=a1x+a2xln(x³)   -------------->> Equation 1

First of all, in command window , type cftool

Figure 1:- cftool (curve fitting toolbox)

The above figure 1 demonstrates the cftool box.

Now, for example 1 , we have to write the values of x and y and write cftool in command window as illustrated in figure 2 so that we can access the x data and y data in curve fitting tool box.