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# 2014-04-08
#
# Matrix operations in R
# an image example
# NOTE: use matrix_image to show the
# correct image plot of a data matrix
# with rows and columns in a consistent
# order
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# use myfunctions to load an image
rm(list=ls())
par(mfrow=c(1,1))
source("scripts/myfunctions.R")
M<-loadppm("data/labrador.ppm")
p<-seq(1,255,1)/255
p<-(p)^0.5
palette<-gray(p)
res<-dim(M)
nrow<-res[1]
ncol<-res[2]
print(paste("size of the n by m matrix: ",nrow," x ",ncol,sep=''))
# the matrix_image function returns the buffer (matrix)
# usedfor plotting the image
buffer<-matrix_image(M,col=palette,main="2-d matrix of brightness intensities")
#filled.contour(x,y,M,col=palette)