Page 174 - Basics of MATLAB and Beyond

xt = x([1 9 10 1]); 1
yt = y([1 9 10 1]); 0.8
xh = x(3:7); 0.6
yh = y(3:7); 0.4
hold on 0.2
0
plot(xt,yt,’k’,xh,yh,’k’) 0 0.5 1
Overlapping patches are drawn in order:
x1=[0110];
y1=[0011];
x2=x1+.5;
y2=y1+.5; 1.5 1.5
clf 1 1
subplot(221)
0.5 0.5
patch(x1,y1,’y’)
patch(x2,y2,’y’) 0 0 0.5 1 1.5 0 0 0.5 1 1.5
subplot(222)
patch(x2,y2,’y’)
patch(x1,y1,’y’)
When patches with holes overlap, the one underneath shows through the
hole:
x = [0 .5 .5 .4 .5 .6 .5 .5 1 .5];
y = [0 0 .1 .2 .3.2 .1 0 0 1];
1.5
x1=x+.5;
y1=y+.2; 1
clf
0.5
patch(x1,y1,’r’)
patch(x,y,’y’) 0 0 0.5 1 1.5
Patches defined by vectors that contain NaNs leave a gap in the edge at
the NaN point and leave the enclosed region unfilled:
t = linspace(0,2*pi,10);
x = cos(t);y = sin(t);
1 1
subplot(221)
0.5 0.5
patch(x,y,’y’)
0 0
x(5) = NaN;y(5) = NaN;
−0.5 −0.5
subplot(222)
−1 −1
patch(x,y,’y’) −1 0 1 −1 0 1
Three-dimensional Patches
Three-dimensional patches are produced by giving the patch command
x, y, and z data. The following generates an inclined triangle:

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