# set terminal pngcairo  transparent enhanced font "arial,10" fontscale 1.0 size 600, 400 
# set output 'igamma.1.png'
set border 3 front lt 0 linecolor 0 linewidth 1.000 dashtype solid
set key fixed right bottom vertical Right noreverse enhanced autotitle nobox
set label 1 "igamma(a,z) = {Γ^{-1}(a) {/*2 ∫@_{/*0.5 0}^{/*.5 z}} {/:Italic t^{a-1}e^{-t}dt}" at graph 0.1, 0.8, 0 left norotate back nopoint
set samples 1000, 1000
set style data lines
set xtics border in scale 1,0.5 nomirror norotate  autojustify
set xtics  norangelimit autofreq  textcolor rgb "black" 
set ytics border in scale 1,0.5 nomirror norotate  autojustify
set ytics  norangelimit 1  textcolor rgb "black" 
set ztics  norangelimit autofreq  textcolor rgb "black" 
set cbtics border in scale 1,0.5 nomirror norotate  autojustify
set cbtics  norangelimit autofreq  textcolor rgb "black" 
set rtics  norangelimit autofreq  textcolor rgb "black" 
set title "igamma domain and convergence improved in version 6" 
set xrange [ 0.990000 : 1.01000 ] noreverse
set yrange [ 0.00000 : 1.00000 ] noreverse
NO_ANIMATION = 1
save_encoding = "utf8"
N = 9
plot for [N=1:9] igamma( 10.**N, x*10.**N ) lw 2          title sprintf("igamma( 10^{%d}, x*10^{%d})",N,N)