# set terminal pngcairo  transparent enhanced font "arial,10" fontscale 1.0 size 600, 400 
# set output 'zeta.3.png'
set border 895 front lt black linewidth 1.000 dashtype solid
set grid nopolar
set grid xtics nomxtics ytics nomytics ztics nomztics nortics nomrtics \
 nox2tics nomx2tics noy2tics nomy2tics nocbtics nomcbtics
set grid vertical layerdefault   lt 0 linecolor 0 linewidth 0.500,  lt 0 linecolor 0 linewidth 0.500
set key fixed left top vertical Right noreverse enhanced autotitle nobox
set samples 201, 201
set isosamples 201, 201
set xyplane relative 0
set title "{/Times=16 Riemann zeta function}    {/Times:Italic=16 ζ(s) = {∑@_{/*0.5 {k=1}}^{/*.5 ∞}}  {/:Italic=12 k^{ -s}}" 
set trange [ * : * ] noreverse nowriteback
set urange [ * : * ] noreverse nowriteback
set vrange [ * : * ] noreverse nowriteback
set xlabel "Real(s)" 
set xlabel  offset character -1, 0, 0 font "" textcolor lt -1 right norotate
set xrange [ -9.00000 : 9.00000 ] noreverse nowriteback
set x2range [ * : * ] noreverse writeback
set ylabel "Imag(s)" 
set yrange [ -9.00000 : 9.00000 ] noreverse nowriteback
set y2range [ * : * ] noreverse writeback
set zrange [ -0.550000 : 0.550000 ] noreverse nowriteback
set cbrange [ * : * ] noreverse writeback
set rrange [ * : * ] noreverse writeback
set pm3d depthorder base
set pm3d interpolate 2,2 flush begin noftriangles noborder corners2color mean
set pm3d lighting primary 0.5 specular 0.1 spec2 0
set palette defined ( 0 0.5451 0 0, 1 1 1 1 )
set colorbox vertical origin screen 0.9, 0.2 size screen 0.05, 0.6 front  noinvert bdefault
unset colorbox
NO_ANIMATION = 1
save_encoding = "utf8"
splot imag( zeta(x + I*y) ) with pm3d title "imag(ζ(s))"