# set terminal pngcairo  transparent enhanced font "arial,10" fontscale 1.0 size 600, 400 
# set output 'function_block.1.png'
unset key
set label 1 "{/Times:Italic=12 Γ(x+iy) }{/Times:Normal=14  = exp(my\\_lngamma(x + y*I))}" at screen 0.5, 0.85, 0 center norotate back nopoint
set view 67, 317, 1, 1
set samples 71, 71
set isosamples 71, 71
set style data lines
set xyplane at 0
set xtics border in scale 1,0.5 mirror norotate  offset character 0, -0.5, 0 autojustify
set xtics  norangelimit 1 
set ytics border in scale 1,0.5 mirror norotate  offset character 0, -0.5, 0 autojustify
set ytics  norangelimit 1 
set title "Example of using code in a function block" 
set title  font "Times,16" textcolor lt -1 norotate
set xlabel "{/Times:Italic=16 x}" 
set xlabel  offset character -3, -1, 0 font "" textcolor lt -1 norotate
set xrange [ -3.50000 : 3.50000 ] noreverse nowriteback
set x2range [ * : * ] noreverse writeback
set ylabel "{/Times:Italic=16 iy}" 
set ylabel  offset character 5, -1, 0 font "" textcolor lt -1 rotate
set yrange [ -3.00000 : 3.00000 ] noreverse nowriteback
set y2range [ * : * ] noreverse writeback
set zrange [ 0.00000 : 7.00000 ] noreverse nowriteback
set cbrange [ * : * ] noreverse writeback
set rrange [ * : * ] noreverse writeback
set pm3d interpolate 1,1 flush begin noftriangles border lt black linewidth 0.500 dashtype solid corners2color mean
unset colorbox
my_lngamma(z) = (z == 0) ? NaN : (real(z) < 0.5) ? $Reflect(z) : $Lancosz(z)
Gamma(z) = exp( my_lngamma(z) )
NO_ANIMATION = 1
array coef[15] = [0.999999999999997,57.1562356658629,-59.5979603554755,14.1360979747417,-0.49191381609762,3.39946499848119e-05,4.65236289270486e-05,-9.83744753048796e-05,0.000158088703224912,-0.000210264441724105,0.000217439618115213,-0.000164318106536764,8.44182239838527e-05,-2.61908384015814e-05,3.68991826595316e-06]
splot abs(Gamma(x + y*I)) with pm3d fc "cyan"