# set terminal pngcairo  transparent enhanced font "arial,10" fontscale 1.0 size 600, 400 
# set output 'named_palettes.1.png'
set samples 41, 41
set isosamples 41, 41
set style data lines
set title "Use hand-constructed 'blues' palette via rgb variable" 
set xrange [ 0.00000 : 5.00000 ] noreverse nowriteback
set x2range [ * : * ] noreverse writeback
set yrange [ 0.00000 : 5.00000 ] noreverse nowriteback
set y2range [ * : * ] noreverse writeback
set zrange [ * : * ] noreverse writeback
set cbrange [ -1.00000 : 1.00000 ] noreverse nowriteback
set rrange [ * : * ] noreverse writeback
set colorbox vertical origin screen 0.9, 0.2 size screen 0.05, 0.6 front  noinvert bdefault
unset colorbox
blues(z) = (z <= blues_min) ? blues[1]          : (z >= blues_max) ? blues[256]          : blues[ floor(255. * (z-blues_min)/(blues_max-blues_min)) + 1]
foo(x,y) = sin(x*y)
NO_ANIMATION = 1
array blues[256] = [127,65919,131712,197504,263297,329089,394882,460674,526467,592259,658052,723844,789637,855429,921222,987014,1052807,1118599,1184392,1250184,1315977,1381769,1447562,1513354,1579147,1644939,1710732,1776524,1842317,1908109,1973902,2039694,2105487,2171279,2237072,2302864,2368657,2434449,2500242,2566034,2631827,2697619,2763412,2829204,2894997,2960789,3026582,3092374,3158167,3223959,3289752,3355544,3421337,3487129,3552922,3618714,3684507,3750299,3816092,3881884,3947677,4013469,4079262,4145054,4210847,4276639,4342432,4408224,4474017,4539809,4605602,4671394,4737187,4802979,4868772,4934564,5000357,5066149,5131942,5197734,5263527,5329319,5395112,5460904,5526697,5592489,5658282,5724074,5789867,5855659,5921452,5987244,6053037,6118829,6184622,6250414,6316207,6381999,6447792,6513584,6579377,6645169,6710962,6776754,6842547,6908339,6974132,7039924,7105717,7171509,7237302,7303094,7368887,7434679,7500472,7566264,7632057,7697849,7763642,7829434,7895227,7961019,8026812,8092604,8158397,8224189,8289982,8355774,8421567,8487359,8553152,8618944,8684737,8750529,8816322,8882114,8947907,9013699,9079492,9145284,9211077,9276869,9342662,9408454,9474247,9540039,9605832,9671624,9737417,9803209,9869002,9934794,10000587,10066379,10132172,10197964,10263757,10329549,10395342,10461134,10526927,10592719,10658512,10724304,10790097,10855889,10921682,10987474,11053267,11119059,11184852,11250644,11316437,11382229,11448022,11513814,11579607,11645399,11711192,11776984,11842777,11908569,11974362,12040154,12105947,12171739,12237532,12303324,12369117,12434909,12500702,12566494,12632287,12698079,12763872,12829664,12895457,12961249,13027042,13092834,13158627,13224419,13290212,13356004,13421797,13487589,13553382,13619174,13684967,13750759,13816552,13882344,13948137,14013929,14079722,14145514,14211307,14277099,14342892,14408684,14474477,14540269,14606062,14671854,14737647,14803439,14869232,14935024,15000817,15066609,15132402,15198194,15263987,15329779,15395572,15461364,15527157,15592949,15658742,15724534,15790327,15856119,15921912,15987704,16053497,16119289,16185082,16250874,16316667,16382459,16448252,16514044,16579837,16645629,16711422,16777215]
blues_min = -1
blues_max = 1
## Last datafile plotted: "++"
splot '++' using 1:2:(foo($1,$2)):(blues(foo($1,$2))) with pm3d lc rgb variable            title "pm3d using 1:2:3:4 with pm3d lc rgb variable"