#
#
############# Spirals.
#

# http://en.wikipedia.org/wiki/Logarithmic_spiral

x <- rnorm(100); hist(x); rm(x)  # <--- resize the graphics window as large as your screen.

r <- .25
theta <- seq(0, 20, by = .01)
length(theta)
x <- as.vector(0)
y <- as.vector(0)
for (i in 1:length(theta)){
x[i] <- (r*theta[i])*cos(theta[i])
y[i] <- (r*theta[i])*sin(theta[i])
plot(x, y, xlim = c(-5,5), ylim = c(-5,5), pch = 20, col = "blue")
}

summary(x)
summary(y)
plot(x,y)

cor(x,y)

rm(i,r,theta,x,y); graphics.off(); ls()


################################################################################

# CAUTION: The script below may induce headaches, blindness, and/or seizures. Use
# at your own risk; the author of this script assumes no liablity for damages, injuries,
# seizures, or any other negative consequences resulting from use of this script.

x <- rnorm(100); hist(x); rm(x)  # <--- resize the graphics window as large as your screen.

library(RColorBrewer)
r <- seq(.25, 2, by = .25)
theta <- seq(0, 20, by = .01)
df <- data.frame(matrix(rep(0,16), ncol = 16))
colores <- brewer.pal(8,"Blues")
for (i in 1:length(theta)){
   df[i,1] <- (r[1]*theta[i])*cos(theta[i])
   df[i,2] <- (r[1]*theta[i])*sin(theta[i])
   plot(df[,1], df[,2], xlim = c(-40,40), ylim = c(-40,40), pch = 20, col = colores[1], xlab = "X", ylab = "Y")
   df[i,3] <- (r[2]*theta[i])*cos(theta[i])
   df[i,4] <- (r[2]*theta[i])*sin(theta[i])
   par(new = T)
   plot(df[,3], df[,4], xlim = c(-40,40), ylim = c(-40,40), pch = 20, col = colores[2], xlab = "X", ylab = "Y")
   df[i,5] <- (r[3]*theta[i])*cos(theta[i])
   df[i,6] <- (r[3]*theta[i])*sin(theta[i])
   par(new = T)
   plot(df[,5], df[,6], xlim = c(-40,40), ylim = c(-40,40), pch = 20, col = colores[3], xlab = "X", ylab = "Y")
   df[i,7] <- (r[4]*theta[i])*cos(theta[i])
   df[i,8] <- (r[4]*theta[i])*sin(theta[i])
   par(new = T)
   plot(df[,7], df[,8], xlim = c(-40,40), ylim = c(-40,40), pch = 20, col = colores[4], xlab = "X", ylab = "Y")
   df[i,9] <- (r[5]*theta[i])*cos(theta[i])
   df[i,10] <- (r[5]*theta[i])*sin(theta[i])
   par(new = T)
   plot(df[,9], df[,10], xlim = c(-40,40), ylim = c(-40,40), pch = 20, col = colores[5], xlab = "X", ylab = "Y")
   df[i,11] <- (r[6]*theta[i])*cos(theta[i])
   df[i,12] <- (r[6]*theta[i])*sin(theta[i])
   par(new = T)
   plot(df[,11], df[,12], xlim = c(-40,40), ylim = c(-40,40), pch = 20, col = colores[6], xlab = "X", ylab = "Y")
   df[i,13] <- (r[7]*theta[i])*cos(theta[i])
   df[i,14] <- (r[7]*theta[i])*sin(theta[i])
   par(new = T)
   plot(df[,13], df[,14], xlim = c(-40,40), ylim = c(-40,40), pch = 20, col = colores[7], xlab = "X", ylab = "Y")
   df[i,15] <- (r[8]*theta[i])*cos(theta[i])
   df[i,16] <- (r[8]*theta[i])*sin(theta[i])
   par(new = T)
   plot(df[,15], df[,16], xlim = c(-40,40), ylim = c(-40,40), pch = 20, col = colores[8], xlab = "X", ylab = "Y")
  }

summary(df)


rm(colores, df, i, r, theta); graphics.off(); ls()
detach("package:RColorBrewer")


# End; April 10, 2012.