[R] Draw Polygon with a Circular Side

[Jim Lemon]

ermimi wrote:
> Hello Friends!!!
> 
> I would want draw a circular histogram, and I would like draw a polygon with
> a circular side. This is easy if I use the functions polygon and arc, but I
> want that the polygon with a circular side have background colour. The
> polygon created with function polygon can have background colour, but the
> surface created with function arc can´t have background colour.
> How I could create a polygon with a circular side that have background
> colour?? 
> Thank you very much,  
> A greetings Luismi

Hi Luismi,
The phrase "circular histogram" brings to mind something like a wind 
rose. There are a few you could try:

windrose in the oce and circular packages

rosavent in the climatol package

oz.windrose in the plotrix package

and perhaps rose in the IDPmisc package

Now about this "polygon with a circular side". I think you mean the 
standard issue polygon like a rectangle except that one side is a 
circular arc instead of a straight line. If this bold conjecture is 
correct, here is an example for you:

plot(0,xlim=c(-1,1),ylim=c(-1,1),xlab="",ylab="",
  type="n",axes=FALSE)
polygon(c(0,-1,-1,0,cos(seq(pi/2,0,length.out=50)),
  cos(seq(2*pi,3*pi/2,length.out=50))),c(-1,-1,1,1,
  sin(seq(pi/2,0,length.out=50)),sin(seq(2*pi,3*pi/2,length.out=50))),
  border="#ffaaaa",col="#66ee33")

Jim