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/*****************************************************************************
* *
* VIRIDIS.SPL Copyright (C) 2021 DSP Development Corporation *
* All Rights Reserved *
* *
* Author: Randy Race *
* *
* Synopsis: Generate a colormap of blue, green, yellow *
* *
* Revisions: 30 Mar 2021 RRR Creation *
* *
*****************************************************************************/
#if @HELP_VIRIDIS
VIRIDIS
Purpose: Generates a colormap of blue, green, yellow.
Syntax: VIRIDIS(len)
len - optional colormap length, defaults to
the length of the current colormap
Returns: A table of RGB triples suitable for the SETCOLORMAP function.
Example:
clen = length(getcolormap());
density(ravel(rep(0..(clen-1), 32), clen)');
viridis;
Creates a table of 32 x colormap length RBG values and
displays the resulting colors. The resulting image is a
vertical plot of colors ranging from blue (lowest) to
green to yellow (highest).
Example:
viridis(256);showcmap
Creates a table of 32 x 256 length RBG values and
displays the resulting colors. The resulting image is a
vertical plot of colors ranging from blue (lowest) to
green to yellow (highest).
Remarks:
VIRIDIS() by itself sets the colormap and shading.
a = viridis() or setcolormap(viridis()) returns the rgb values.
In this case, use SETSHADING to make the new colormap
take effect on an existing density or 2D plot.
The colormap is meant do provide better color separation for
viewers with some forms of color blindness.
See Also:
Autumn
Bone
Cool
Copper
Gray
Hot
Hsv
Pink
Rainbow
Setcolormap
Setshading
Showcmap
Spring
Summer
Winter
#endif
/* viridis colormap */
viridis(cmaplen)
{
local rgb;
if (argc < 1)
{
cmaplen = length(getcolormap());
}
/* RGB colors */
rgb =
{
{0.267004, 0.004874, 0.329415},
{0.268510, 0.009605, 0.335427},
{0.269944, 0.014625, 0.341379},
{0.271305, 0.019942, 0.347269},
{0.272594, 0.025563, 0.353093},
{0.273809, 0.031497, 0.358853},
{0.274952, 0.037752, 0.364543},
{0.276022, 0.044167, 0.370164},
{0.277018, 0.050344, 0.375715},
{0.277941, 0.056324, 0.381191},
{0.278791, 0.062145, 0.386592},
{0.279566, 0.067836, 0.391917},
{0.280267, 0.073417, 0.397163},
{0.280894, 0.078907, 0.402329},
{0.281446, 0.084320, 0.407414},
{0.281924, 0.089666, 0.412415},
{0.282327, 0.094955, 0.417331},
{0.282656, 0.100196, 0.422160},
{0.282910, 0.105393, 0.426902},
{0.283091, 0.110553, 0.431554},
{0.283197, 0.115680, 0.436115},
{0.283229, 0.120777, 0.440584},
{0.283187, 0.125848, 0.444960},
{0.283072, 0.130895, 0.449241},
{0.282884, 0.135920, 0.453427},
{0.282623, 0.140926, 0.457517},
{0.282290, 0.145912, 0.461510},
{0.281887, 0.150881, 0.465405},
{0.281412, 0.155834, 0.469201},
{0.280868, 0.160771, 0.472899},
{0.280255, 0.165693, 0.476498},
{0.279574, 0.170599, 0.479997},
{0.278826, 0.175490, 0.483397},
{0.278012, 0.180367, 0.486697},
{0.277134, 0.185228, 0.489898},
{0.276194, 0.190074, 0.493001},
{0.275191, 0.194905, 0.496005},
{0.274128, 0.199721, 0.498911},
{0.273006, 0.204520, 0.501721},
{0.271828, 0.209303, 0.504434},
{0.270595, 0.214069, 0.507052},
{0.269308, 0.218818, 0.509577},
{0.267968, 0.223549, 0.512008},
{0.266580, 0.228262, 0.514349},
{0.265145, 0.232956, 0.516599},
{0.263663, 0.237631, 0.518762},
{0.262138, 0.242286, 0.520837},
{0.260571, 0.246922, 0.522828},
{0.258965, 0.251537, 0.524736},
{0.257322, 0.256130, 0.526563},
{0.255645, 0.260703, 0.528312},
{0.253935, 0.265254, 0.529983},
{0.252194, 0.269783, 0.531579},
{0.250425, 0.274290, 0.533103},
{0.248629, 0.278775, 0.534556},
{0.246811, 0.283237, 0.535941},
{0.244972, 0.287675, 0.537260},
{0.243113, 0.292092, 0.538516},
{0.241237, 0.296485, 0.539709},
{0.239346, 0.300855, 0.540844},
{0.237441, 0.305202, 0.541921},
{0.235526, 0.309527, 0.542944},
{0.233603, 0.313828, 0.543914},
{0.231674, 0.318106, 0.544834},
{0.229739, 0.322361, 0.545706},
{0.227802, 0.326594, 0.546532},
{0.225863, 0.330805, 0.547314},
{0.223925, 0.334994, 0.548053},
{0.221989, 0.339161, 0.548752},
{0.220057, 0.343307, 0.549413},
{0.218130, 0.347432, 0.550038},
{0.216210, 0.351535, 0.550627},
{0.214298, 0.355619, 0.551184},
{0.212395, 0.359683, 0.551710},
{0.210503, 0.363727, 0.552206},
{0.208623, 0.367752, 0.552675},
{0.206756, 0.371758, 0.553117},
{0.204903, 0.375746, 0.553533},
{0.203063, 0.379716, 0.553925},
{0.201239, 0.383670, 0.554294},
{0.199430, 0.387607, 0.554642},
{0.197636, 0.391528, 0.554969},
{0.195860, 0.395433, 0.555276},
{0.194100, 0.399323, 0.555565},
{0.192357, 0.403199, 0.555836},
{0.190631, 0.407061, 0.556089},
{0.188923, 0.410910, 0.556326},
{0.187231, 0.414746, 0.556547},
{0.185556, 0.418570, 0.556753},
{0.183898, 0.422383, 0.556944},
{0.182256, 0.426184, 0.557120},
{0.180629, 0.429975, 0.557282},
{0.179019, 0.433756, 0.557430},
{0.177423, 0.437527, 0.557565},
{0.175841, 0.441290, 0.557685},
{0.174274, 0.445044, 0.557792},
{0.172719, 0.448791, 0.557885},
{0.171176, 0.452530, 0.557965},
{0.169646, 0.456262, 0.558030},
{0.168126, 0.459988, 0.558082},
{0.166617, 0.463708, 0.558119},
{0.165117, 0.467423, 0.558141},
{0.163625, 0.471133, 0.558148},
{0.162142, 0.474838, 0.558140},
{0.160665, 0.478540, 0.558115},
{0.159194, 0.482237, 0.558073},
{0.157729, 0.485932, 0.558013},
{0.156270, 0.489624, 0.557936},
{0.154815, 0.493313, 0.557840},
{0.153364, 0.497000, 0.557724},
{0.151918, 0.500685, 0.557587},
{0.150476, 0.504369, 0.557430},
{0.149039, 0.508051, 0.557250},
{0.147607, 0.511733, 0.557049},
{0.146180, 0.515413, 0.556823},
{0.144759, 0.519093, 0.556572},
{0.143343, 0.522773, 0.556295},
{0.141935, 0.526453, 0.555991},
{0.140536, 0.530132, 0.555659},
{0.139147, 0.533812, 0.555298},
{0.137770, 0.537492, 0.554906},
{0.136408, 0.541173, 0.554483},
{0.135066, 0.544853, 0.554029},
{0.133743, 0.548535, 0.553541},
{0.132444, 0.552216, 0.553018},
{0.131172, 0.555899, 0.552459},
{0.129933, 0.559582, 0.551864},
{0.128729, 0.563265, 0.551229},
{0.127568, 0.566949, 0.550556},
{0.126453, 0.570633, 0.549841},
{0.125394, 0.574318, 0.549086},
{0.124395, 0.578002, 0.548287},
{0.123463, 0.581687, 0.547445},
{0.122606, 0.585371, 0.546557},
{0.121831, 0.589055, 0.545623},
{0.121148, 0.592739, 0.544641},
{0.120565, 0.596422, 0.543611},
{0.120092, 0.600104, 0.542530},
{0.119738, 0.603785, 0.541400},
{0.119512, 0.607464, 0.540218},
{0.119423, 0.611141, 0.538982},
{0.119483, 0.614817, 0.537692},
{0.119699, 0.618490, 0.536347},
{0.120081, 0.622161, 0.534946},
{0.120638, 0.625828, 0.533488},
{0.121380, 0.629492, 0.531973},
{0.122312, 0.633153, 0.530398},
{0.123444, 0.636809, 0.528763},
{0.124780, 0.640461, 0.527068},
{0.126326, 0.644107, 0.525311},
{0.128087, 0.647749, 0.523491},
{0.130067, 0.651384, 0.521608},
{0.132268, 0.655014, 0.519661},
{0.134692, 0.658636, 0.517649},
{0.137339, 0.662252, 0.515571},
{0.140210, 0.665859, 0.513427},
{0.143303, 0.669459, 0.511215},
{0.146616, 0.673050, 0.508936},
{0.150148, 0.676631, 0.506589},
{0.153894, 0.680203, 0.504172},
{0.157851, 0.683765, 0.501686},
{0.162016, 0.687316, 0.499129},
{0.166383, 0.690856, 0.496502},
{0.170948, 0.694384, 0.493803},
{0.175707, 0.697900, 0.491033},
{0.180653, 0.701402, 0.488189},
{0.185783, 0.704891, 0.485273},
{0.191090, 0.708366, 0.482284},
{0.196571, 0.711827, 0.479221},
{0.202219, 0.715272, 0.476084},
{0.208030, 0.718701, 0.472873},
{0.214000, 0.722114, 0.469588},
{0.220124, 0.725509, 0.466226},
{0.226397, 0.728888, 0.462789},
{0.232815, 0.732247, 0.459277},
{0.239374, 0.735588, 0.455688},
{0.246070, 0.738910, 0.452024},
{0.252899, 0.742211, 0.448284},
{0.259857, 0.745492, 0.444467},
{0.266941, 0.748751, 0.440573},
{0.274149, 0.751988, 0.436601},
{0.281477, 0.755203, 0.432552},
{0.288921, 0.758394, 0.428426},
{0.296479, 0.761561, 0.424223},
{0.304148, 0.764704, 0.419943},
{0.311925, 0.767822, 0.415586},
{0.319809, 0.770914, 0.411152},
{0.327796, 0.773980, 0.406640},
{0.335885, 0.777018, 0.402049},
{0.344074, 0.780029, 0.397381},
{0.352360, 0.783011, 0.392636},
{0.360741, 0.785964, 0.387814},
{0.369214, 0.788888, 0.382914},
{0.377779, 0.791781, 0.377939},
{0.386433, 0.794644, 0.372886},
{0.395174, 0.797475, 0.367757},
{0.404001, 0.800275, 0.362552},
{0.412913, 0.803041, 0.357269},
{0.421908, 0.805774, 0.351910},
{0.430983, 0.808473, 0.346476},
{0.440137, 0.811138, 0.340967},
{0.449368, 0.813768, 0.335384},
{0.458674, 0.816363, 0.329727},
{0.468053, 0.818921, 0.323998},
{0.477504, 0.821444, 0.318195},
{0.487026, 0.823929, 0.312321},
{0.496615, 0.826376, 0.306377},
{0.506271, 0.828786, 0.300362},
{0.515992, 0.831158, 0.294279},
{0.525776, 0.833491, 0.288127},
{0.535621, 0.835785, 0.281908},
{0.545524, 0.838039, 0.275626},
{0.555484, 0.840254, 0.269281},
{0.565498, 0.842430, 0.262877},
{0.575563, 0.844566, 0.256415},
{0.585678, 0.846661, 0.249897},
{0.595839, 0.848717, 0.243329},
{0.606045, 0.850733, 0.236712},
{0.616293, 0.852709, 0.230052},
{0.626579, 0.854645, 0.223353},
{0.636902, 0.856542, 0.216620},
{0.647257, 0.858400, 0.209861},
{0.657642, 0.860219, 0.203082},
{0.668054, 0.861999, 0.196293},
{0.678489, 0.863742, 0.189503},
{0.688944, 0.865448, 0.182725},
{0.699415, 0.867117, 0.175971},
{0.709898, 0.868751, 0.169257},
{0.720391, 0.870350, 0.162603},
{0.730889, 0.871916, 0.156029},
{0.741388, 0.873449, 0.149561},
{0.751884, 0.874951, 0.143228},
{0.762373, 0.876424, 0.137064},
{0.772852, 0.877868, 0.131109},
{0.783315, 0.879285, 0.125405},
{0.793760, 0.880678, 0.120005},
{0.804182, 0.882046, 0.114965},
{0.814576, 0.883393, 0.110347},
{0.824940, 0.884720, 0.106217},
{0.835270, 0.886029, 0.102646},
{0.845561, 0.887322, 0.099702},
{0.855810, 0.888601, 0.097452},
{0.866013, 0.889868, 0.095953},
{0.876168, 0.891125, 0.095250},
{0.886271, 0.892374, 0.095374},
{0.896320, 0.893616, 0.096335},
{0.906311, 0.894855, 0.098125},
{0.916242, 0.896091, 0.100717},
{0.926106, 0.897330, 0.104071},
{0.935904, 0.898570, 0.108131},
{0.945636, 0.899815, 0.112838},
{0.955300, 0.901065, 0.118128},
{0.964894, 0.902323, 0.123941},
{0.974417, 0.903590, 0.130215},
{0.983868, 0.904867, 0.136897},
{0.993248, 0.906157, 0.143936}
};
/* interpolate to colormap size */
rgb = xylookup(1..length(rgb), rgb, linspace(1, length(rgb), cmaplen));
/* remove X columns */
rgb = rgb[.., 1..2..6];
if (outargc == 0)
{
/* set the colormap and shading */
setplotshading(rgb);
}
else
{
/* return the colormap */
setrgbprops(rgb);
return(rgb);
}
}