integrate
Integrate cfit object
Syntax
int = integrate(fun,x,x0)
Description
int = integrate(fun,x,x0) integrates the
cfit object fun at the points specified by
the vector x, starting from x0, and returns
the result in int. int is a vector the same
size as x. x0 is a scalar.
Examples
Create a baseline sinusoidal signal:
xdata = (0:.1:2*pi)'; y0 = sin(xdata);
Add response-dependent Gaussian noise to the signal:
noise = 2*y0.*randn(size(y0)); ydata = y0 + noise;
Fit the noisy data with a custom sinusoidal model:
f = fittype('a*sin(b*x)');
fit1 = fit(xdata,ydata,f,'StartPoint',[1 1]);Find the integral of the fit at the predictors:
int = integrate(fit1,xdata,0);
Plot the data, the fit, and the integral:
subplot(2,1,1)
plot(fit1,xdata,ydata) % cfit plot method
subplot(2,1,2)
plot(xdata,int,'m') % double plot method
grid on
legend('integral')
Note that integrals can also be computed and plotted directly with the
cfit
plot method, as follows:
plot(fit1,xdata,ydata,{'fit','integral'})The plot method, however, does not return data on the
integral.
See Also
differentiate | fit | plot