[R] [OOPS!]Sexy Little Number :-)-O

[Barry Rowlingson]

2008/10/5 Ted Harding <Ted.Harding at manchester.ac.uk>:

> sexyNo()

 How puerile. R should be used for serious purposes. Here is a plot
that shows a log-log-log feasible region symmetric about x=0, within a
sinusoidal left and right-bound envelope:

# set up plot
xrange=c(-15,15)
yrange=c(0,16)
plot(0,xlim=xrange,ylim=yrange,type='n')

# draw outer envelope
yr=seq(yrange[1],yrange[2],len=50)
offsetFn=function(y){2*sin(0+y/3)}
offset=offsetFn(yr)
leftE = function(y){-10-offsetFn(y)}
rightE = function(y){10+offsetFn(y)}


xp=c(leftE(yr),rev(rightE(yr)))
yp=c(yr,rev(yr))
polygon(xp,yp,col="#ffeecc",border=NA)

#abline(v=0)

# feasible region upper limit:
h=9

# left and right defined by triple-log function:
xt=seq(0,rightE(h),len=100)
yt=log(1+log(1+log(xt+1)))
yt=yt-min(yt)
yt=h*yt/max(yt)

x=c(leftE(h),rightE(h),rev(xt),-xt)
y=c(h,h,rev(yt),yt)
polygon(x,y,col="red",border=NA)