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...uot;#FEECCE" I do not have a great way of confirming that the conversion is correct with my changes, but I did verify that the `M` matrix computed within`grDevics:::chromaticAdaptation` for the "D65"->"D50" conversion (approximately) matches the corresponding matrix from brucelindbloom.com chromatic adaptation page: http://www.brucelindbloom.com/Eqn_ChromAdapt.html Additionally visual inspection via ??? scales::show_col(c(rgb.in, rgb(clr.out))) is consistent with a shift from bluer indirect daylight ("D65") to yellower direct daylight ("D50") illuminant. It i...

grDevices::convertColor has arguments 'from' and 'to' which can take on value 'XYZ'. Can someone confirm that 'XYZ' is the same as the CIE chromaticity coordinates that are also sometimes refered to as 'xyY' in the literature? Or are these the CIE tristimulus values? It looks to me like the first case is true, but I would appreciate hearing from one of

...0.734 0.699 2.5Y 0.8 2 0.479 0.439 0.943 2.5Y 0.8 4 0.82 0.64 0.943 2.5Y 1 2 0.4362 0.4177 1.21 I have converted xyY coordinates to XYZ coordinates, based on the equations presented here: http://www.brucelindbloom.com/index.html?ColorCalcHelp.html #read in the soil colors: munsell + xyY soil <- read.table("soil_colors", header=F, col.names=c("H","V","C","x","y","Y")) #convert to XYZ X <- (soil$x * soil$Y ) / soil$y Y <- soil$Y...