Re: Shade region between curves

[Rob Mahurin]

On May 19, 2009, at 5:56 PM, Xin Dong wrote:
> Hi Rob,
>
> Can you explain x(end:-1:1)? What does that mean?

x(1:end) means all the elements of x, in order.
x(1:2:end) means the first, third, fifth, etc. elements of x.
x(end:-1:1) means all the elements of x, in reverse order.

patch() makes a closed curve and shades the inside.  Without  
reversing the direction of the second curve there is an extra line  
and the shaded area is different.  Try making a curve only four  
points to see.

Cheers,
Rob

> On Tue, May 19, 2009 at 12:25 PM, Rob Mahurin <address@hidden> wrote:
>
> > On Tue, May 19, 2009 at 3:48 PM, ofeyrpf <address@hidden>  
> > wrote:
> > > Is it possible with Octave to shade a region between two graphs?
> >
> > On May 19, 2009, at 11:17 AM, Michael Goffioul wrote:
> > > What you're probably looking for is called "area".
> >
> >
> > "area" shades between a curve and the x-axis.  You can shade between
> > two curves with "patch":
> >
> > octave:13> x = linspace(0,1.5);
> > octave:14> patch( [x, x(end:-1:1)], [x.^2, x(end:-1:1).^4] , [1 0 0])
> >
> > There may be an easier way that other people know about.
> >
> > Rob
> >
> > --
> > Rob Mahurin
> > Department of Physics and Astronomy
> > University of Tennessee                 865 207 2594
> > Knoxville, TN 37996                     address@hidden
> >
> >
> >
> > _______________________________________________
> > Help-octave mailing list
> > address@hidden
> > https://www-old.cae.wisc.edu/mailman/listinfo/help-octave

Rob

--
Rob Mahurin
Department of Physics and Astronomy
University of Tennessee                 865 207 2594
Knoxville, TN 37996                     address@hidden