Nothing
transfMatrix = function(angle=0, offset=c(0,0) )
{
#---------------------------------------------------------------------------
#
# Builds a simple transformation matrix as the concatenation of rotation
# and translation for 2D at the present. Note that this is an affine
# transformation so we use homogeneous coordinates.
#
# Note that translation follows rotation the way this is set up currently.
#
# Also, we set this up so that we can PRE-multiply by a matrix of
# coordinates to be transformed with columns in the form; [x, y, 1]
# One can always transpose to post-multiply coordinates.
#
# Arguments...
# angle = the angle for rotation: positive = counter clockwise
# offset = the amount to translate for (x,y)
#
# Returns...
# the transformatin matrix--returns identity by default
#
#Author... Date: 27-Apr-2010
# Jeffrey H. Gove
# USDA Forest Service
# Northern Research Station
# 271 Mast Road
# Durham, NH 03824
# jhgove@unh.edu
# phone: 603-868-7667 fax: 603-868-7604
#---------------------------------------------------------------------------
#
# translation matrix...
#
tm = diag(3)
tm[3,1:2] = offset
#
# rotation matrix...
#
rot = diag(3)
rot[1,1] = cos(angle)
rot[2,1] = -sin(angle)
rot[1,2] = -rot[2,1]
rot[2,2] = rot[1,1]
#
# concatenate, translation follows rotation...
#
transf = rot%*%tm
return(transf)
} #transfMatrix
Any scripts or data that you put into this service are public.
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.