Andrews curves can be plotted to visualize multidimensional data. The option clr is used to specify the column number to be used for color.
> andrews(iris,clr=5,ymax=3) # column number 5 (Species) is used for color
The plot shows that one species (red) is more separate from other the other two.
Similar separation is not there in birthwt dataset (using 'low' variable for color):
> andrews(birthwt[-10],clr=1, ymax=4) # 10th column (i.e. bwt) is excluded
Jaroslav Myslivec (2012). andrews: Andrews curves. R package version 1.0. http://CRAN.R-project.org/package=andrews