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gnuplot demo script: heatmaps.dem

autogenerated by webify.pl on Tue Apr 22 15:17:01 2014
gnuplot version gnuplot 5.0 patchlevel alpha
#
# Two ways of generating a 2D heat map from ascii data
#

set title "Heat Map generated from a file containing Z values only"
unset key
set tic scale 0

# Color runs from white to green
set palette rgbformula -7,2,-7
set cbrange [0:5]
set cblabel "Score"
unset cbtics

set xrange [-0.5:4.5]
set yrange [-0.5:4.5]

$map1 << EOD
5 4 3 1 0
2 2 0 0 1
0 0 0 1 0
0 0 0 2 3
0 1 2 4 3
EOD

set view map
splot '$map1' matrix with image


Click here for minimal script to generate this plot




set title "Heat Map generated by 'plot' from a stream of XYZ values"\
         ."\nNB: Rows must be separated by blank lines!"

$map2 << EOD
0 0 5
0 1 4
0 2 3
0 3 1
0 4 0

1 0 2
1 1 2
1 2 0
1 3 0
1 4 1

2 0 0
2 1 0
2 2 0
2 3 1
2 4 0

3 0 0
3 1 0
3 2 0
3 3 2
3 4 3

4 0 0
4 1 1
4 2 2
4 3 4
4 4 3
EOD 

plot '$map2' using 2:1:3 with image


Click here for minimal script to generate this plot




set title "Heat map with non-zero pixel values written as labels"
plot $map1 matrix using 1:2:3 with image, \
     $map1 matrix using 1:2:($3 == 0 ? "" : sprintf("%g",$3) ) with labels


Click here for minimal script to generate this plot




# Some output modes (SVG, HTML5) allow smoothing of adjacent pixels,
# which may not be desired. This is not normally an issue with PNG or PDF.
# The `pixels` option forces pixel-by-pixel drawing with no smoothing.

unset colorbox
set format xy ""
set multiplot layout 1,2 title "Compare 'image' and 'image pixels' modes" \
    margin 0.05, 0.95, 0.10, 0.85 spacing 0.05
set title "plot with image"
plot $map1 matrix using 1:2:3 with image
set title "plot with image pixels"
plot $map1 matrix using 1:2:3 with image pixels
unset multiplot


Click here for minimal script to generate this plot





#
# Demonstrate use of 4th data column to color a 3D surface.
# Also demonstrate use of the pseudodata special file '++'.
# This plot is nice for exploring the effect of the 'l' and 'L' hotkeys.
#
set view 49, 28, 1, 1.48
set xrange [ 5 : 35 ] noreverse nowriteback
set yrange [ 5 : 35 ] noreverse nowriteback
# set zrange [ 1.0 : 3.0 ] noreverse nowriteback
set ticslevel 0
set format cb "%4.1f"
set colorbox user size .03, .6 noborder
set cbtics scale 0

set samples 25, 25
set isosamples 50, 50

set title "4D data (3D Heat Map)"\
          ."\nIndependent value color-mapped onto 3D surface"  offset 0,1
set xlabel "x" offset 3, 0, 0 
set ylabel "y" offset -5, 0, 0
set zlabel "z" offset 2, 0, 0 
set pm3d implicit at s

Z(x,y) = 100. * (sinc(x,y) + 1.5)
sinc(x,y) = sin(sqrt((x-20.)**2+(y-20.)**2))/sqrt((x-20.)**2+(y-20.)**2)
color(x,y) = 10. * (1.1 + sin((x-20.)/5.)*cos((y-20.)/10.))

splot '++' using 1:2:(Z($1,$2)):(color($1,$2)) with pm3d title "4 data columns x/y/z/color"


Click here for minimal script to generate this plot




set title "4D data (3D Heat Map)"\
          ."\nZ is contoured. Independent value is color-mapped"  offset 0,1

set view map
set ylabel norotate offset -1,0

set contour base
splot '++' using 1:2:(Z($1,$2)):(color($1,$2)) with pm3d title "4 data columns x/y/z/color"


Click here for minimal script to generate this plot




# Release datablocks used in this demo
undefine $map1 $map2