Re: peaks and valleys plot

[Ben Abbott]

On Dec 30, 2011, at 7:08 PM, Rick T wrote:

> Greetings All
> 
> I'm trying to have the x value and y value next to the peak and valley on a 
> plot can someone assist
> 
> t= linspace(0,2*pi,8000); 
> freq=10;
> y=sin(t*freq)+cos(t*freq*1.3); 
> y=y';
> y2=y*3+y*4+y*2;
> yf=(y2(:,1)/max(abs(y2(:,1)))*1); %keep at 1, amplitude levels 
> plot(yf)

I haven't tested this.

[~, mn] = min (yf);
[~, mx] = max (yf);
plot (t, yf, t(mn), yf(mn), "s", t(mx), yf(mx), "s")
text (t(mn), yf(mn), sprintf ("min = %f", yf(mn)), "verticalalignment", "top", 
"horizontalalighment", "center")
text (t(mx), yf(mx), sprintf ("max = %f", yf(mx)), "verticalalignment", 
"bottom", "horizontalalighment", "center")

Ben