MATLAB Central Newsreader - Wrap a plot?

Wrap a plot?

David Doria — Wed, 04 Jun 2008 18:35:10 -0400

I have values of x between 0 and 360 (angles). I have values
corresponding to those angles in y.

for example
x = [1 4.5 7 9.8];
y = [1 2 3 4];

I am interested in what happens at the 0/360 line, and now
those things are on opposite sides of the plot. I'd like to
have the plot like this

270....360/0...90

rather than

0....180....360

Is there a way to specify this in the plot properties?

Thanks,
Dave

Re: Wrap a plot?

roberson@ibd.nrc-cnrc.gc.ca (Walter Roberson) — Wed, 04 Jun 2008 19:04:40 -0400

In article <g26n8u$mhd$1@fred.mathworks.com>,
David Doria <daviddoria@gmail.com> wrote:
>I have values of x between 0 and 360 (angles). I have values
>corresponding to those angles in y.

>for example
>x = [1 4.5 7 9.8];
>y = [1 2 3 4];

>I am interested in what happens at the 0/360 line, and now
>those things are on opposite sides of the plot. I'd like to
>have the plot like this

>270....360/0...90

>rather than

>0....180....360

>Is there a way to specify this in the plot properties?

No. But you can

xph = x >= 270 & x < 360;
xpl = x >= 0 & x <= 90;
plot([x(xph),360+x(xpl)], y([xph xpl]) );

and then set the XTick to [270:step:450]
and set the XTickLabels to [270:step:360-step 0:step:90]
for appropriate step size.

--
Q: Why did the chicken cross the Mobius strip?

A: There were manifold reasons.

Re: Wrap a plot?

us — Wed, 04 Jun 2008 19:09:02 -0400

"David Doria":
<SNIP axis acrobatics...

one of the solutions

% the data
     x=0:45:360;
     y=x+25*(rand(size(x))-.5);
     xc=270;
% the plot
     ix=find(x>=xc,1,'first'); % FP issues
     ix=[ix:numel(x),1:ix-1];
     plot(x,y(ix),'o-r');
     set(gca,...
        'xtick',x,...
        'xticklabel',x(ix));

us