# This example shows how a nonlinear axis definition can be used to 

# set up "probability axis" scaling on both the x and y axes.

# This is also known as "probit" scaling.

# We compare 3 treatments of an image file (Tux).

# They differ in the sigma value defining the normal distribution curve

# used for scaling.

# The 4th plot shows the original, unscaled image using linear axes.

#

unset border

set title offset 0,-1

set multiplot layout 2,2 title "Probability axes:  Scale image pixels by distance from center treated as a Z-score"

set title "Sigma = 22 pixels"

sigma = 22.

ticinterval = 2

load 'probably_tux.dem'

set title "Sigma = 30 pixels"

sigma = 30.

ticinterval = 1

load 'probably_tux.dem'

set title "Sigma = 60 pixels"

sigma = 60.

load 'probably_tux.dem'

set title "Linear Scale"

set label 1 "Tux"

set xlabel "   "

set ylabel "   "

unset nonlinear x

unset nonlinear y

unset xtics

unset ytics

replot

unset multiplot

pause -1 "<cr> to continue"

reset