# set terminal pngcairo  transparent enhanced font "arial,10" fontscale 1.0 size 600, 400 
# set output 'BesselK.3.png'
set view 42, 33, 1, 1
set samples 201, 201
set isosamples 201, 201
set hidden3d back offset 1 trianglepattern 3 undefined 1 altdiagonal bentover
set style data lines
set xyplane relative 0
set title "Modified Bessel functions of the second kind" 
set xlabel "x" 
set xrange [ -5.00000 : 5.00000 ] noreverse nowriteback
set x2range [ * : * ] noreverse writeback
set ylabel "iy" 
set yrange [ -5.00000 : 5.00000 ] noreverse nowriteback
set y2range [ * : * ] noreverse writeback
set zrange [ -10.0000 : 5.00000 ] noreverse writeback
set cbrange [ * : * ] noreverse writeback
set rrange [ * : * ] noreverse writeback
set pm3d lighting primary 0.5 specular 0.2 spec2 0.6
set pm3d spotlight rgb 0xff0044 rot_x 50 rot_z 90 Phong 4.0
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(BesselK(0, (x+y*I))) lw .2 with pm3d fc "gray"