The 40 Munsell hues are typically arranged from 5R to 2.5R moving clock wise on the unit circle. This function matches a vector of hues to positions on that circle, with options for setting a custom origin or search direction.

This function is fully vectorized.

huePosition(
x,
returnHues = FALSE,
includeNeutral = FALSE,
origin = "5R",
direction = c("cw", "ccw")
)

## Arguments

x character vector of hues, e.g. c('10YR', '5YR'), optional if returnHues = TRUE logical, should the full set of Munsell hues be returned? See details. logical, add 'N' to the end of the full set of Munsell hues hue to be used as the starting point for position searches (position 1) indexing direction, should be cw (clock wise) or ccw (counter-clock wise)

## Value

A vector of integer hue positions is returned, of the same length and order as x. If returnHues = TRUE, then all hue names and ordering are returned and x is ignored.

## References

https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ref/?cid=nrcs142p2_053569

Munsell book of color. 1976. Macbeth, a Division of Kollmorgen Corp., Baltimore, MD.

D.E. Beaudette

## Examples


# get hue ordering for setting levels of a factor
huePosition(returnHues = TRUE)
#>  [1] "5R"    "7.5R"  "10R"   "2.5YR" "5YR"   "7.5YR" "10YR"  "2.5Y"  "5Y"
#> [10] "7.5Y"  "10Y"   "2.5GY" "5GY"   "7.5GY" "10GY"  "2.5G"  "5G"    "7.5G"
#> [19] "10G"   "2.5BG" "5BG"   "7.5BG" "10BG"  "2.5B"  "5B"    "7.5B"  "10B"
#> [28] "2.5PB" "5PB"   "7.5PB" "10PB"  "2.5P"  "5P"    "7.5P"  "10P"   "2.5RP"
#> [37] "5RP"   "7.5RP" "10RP"  "2.5R"

# get hue ordering including N (neutral)
huePosition(returnHues = TRUE, includeNeutral = TRUE)
#>  [1] "5R"    "7.5R"  "10R"   "2.5YR" "5YR"   "7.5YR" "10YR"  "2.5Y"  "5Y"
#> [10] "7.5Y"  "10Y"   "2.5GY" "5GY"   "7.5GY" "10GY"  "2.5G"  "5G"    "7.5G"
#> [19] "10G"   "2.5BG" "5BG"   "7.5BG" "10BG"  "2.5B"  "5B"    "7.5B"  "10B"
#> [28] "2.5PB" "5PB"   "7.5PB" "10PB"  "2.5P"  "5P"    "7.5P"  "10P"   "2.5RP"
#> [37] "5RP"   "7.5RP" "10RP"  "2.5R"  "N"

# get position of the '10YR' hue, relative to standard origin of '5R'
# should be 7
huePosition(x = '10YR')
#> [1] 7

# get position of the '10YR' hue, relative to standard origin of '5YR'
# should be 3
huePosition(x = '10YR', origin = '5YR')
#> [1] 3

# visualize
op <- par(mar = c(0, 0, 0, 0), fg = 'white', bg = 'black')

huePositionCircle(huePosition(returnHues = TRUE, origin = '5YR'))

par(op)