the plots we shall also need a function that returns the model. Both the model and the sum of squares functions are easy to write as one line anonymous functions using the @ construct.</p><pre class="codeinput">modelfun = @(x,theta) theta(1)*x./(theta(2)+x);
ssfun    = @(theta,data) sum((data.ydata-modelfun(data.xdata,theta)).^2);
</pre><p>In this case the initial values for the parameters are easy to guess by looking at the plotted data. As we alredy have the sum-of-squares function, we might as well try t