Simulate plausible soil colors based on several possible parameterization of a "range in characteristics" (RIC). Soil color RIC can be specified by a list of parameters:

  • soil color proportions, as output from aggregateColor() -- method = 'proportions'

  • most likely Munsell color, CIE2000 threshold, and vector of acceptable hues -- method = 'dE00'

  • data.frame of Munsell hue, value, and chroma representing observed soil colors -- method = 'mvnorm'

simulateColor(
  method = c("dE00", "proportions", "mvnorm"),
  n,
  parameters,
  SPC = NULL
)

Arguments

method

simulation method, see details

n

number of simulated colors per group

parameters

a list, format depends on method:

  • proportions: output from aggregateColor()

  • dE00: formatted as list(m = '7.5YR 3/3', thresh = 5, hues = c('7.5YR'))

  • mvnorm: formatted as list(hvc = x)

Where m is a single representative Munsell chip, thresh is a threshold specified in CIE2000 color contrast (dE00), hues is a vector of allowed Munsell hues, and x is a data.frame representing columns of Munsell hue, value, and chroma having at least 3 rows.

SPC

SoilProfileCollection, attempt to modify SPC with simulated colors

Value

a list, unless SPC is specified, then a SoilProfileCollection object

Author

D.E. Beaudette

Examples


# restrict examples to 2 cores
data.table::setDTthreads(Sys.getenv("OMP_THREAD_LIMIT", unset = 2))

# m: representative or most likely color
# thresh: dE00 threshold
# hues: allowed Munsell hues
p <- list(
  'A' = list(m = '7.5YR 3/3', thresh = 5, hues = c('7.5YR')),
  'BA' = list(m = '7.5YR 4/4', thresh = 8, hues = c('7.5YR')),
  'Bt1' = list(m = '7.5YR 4/4', thresh = 8, hues = c('5YR', '7.5YR')),
  'Bt2' = list(m = '5YR 4/5', thresh = 8, hues = c('5YR', '7.5YR')),
  'Bt3' = list(m = '10YR 4/6', thresh = 10, hues = c('10YR', '7.5YR')),
  'Cr' = list(m = '2.5G 6/2', thresh = 15, hues = c('2.5G', '2.5GY', '2.5BG'))
)

# simulate
(cols <- simulateColor(method = 'dE00', n = 10, parameters = p))
#> $A
#>  [1] "7.5YR 3/4" "7.5YR 3/3" "7.5YR 3/4" "7.5YR 3/3" "7.5YR 3/3" "7.5YR 3/3"
#>  [7] "7.5YR 3/4" "7.5YR 3/2" "7.5YR 3/3" "7.5YR 3/3"
#> 
#> $BA
#>  [1] "7.5YR 4/5" "7.5YR 4/6" "7.5YR 4/4" "7.5YR 4/3" "7.5YR 4/4" "7.5YR 4/6"
#>  [7] "7.5YR 4/4" "7.5YR 4/3" "7.5YR 4/2" "7.5YR 4/5"
#> 
#> $Bt1
#>  [1] "7.5YR 4/7" "5YR 4/4"   "5YR 4/4"   "5YR 4/5"   "7.5YR 4/5" "7.5YR 4/6"
#>  [7] "5YR 4/5"   "7.5YR 4/4" "7.5YR 4/5" "5YR 4/3"  
#> 
#> $Bt2
#>  [1] "7.5YR 4/4" "5YR 4/5"   "5YR 4/6"   "5YR 4/5"   "7.5YR 4/3" "7.5YR 4/4"
#>  [7] "5YR 4/7"   "5YR 4/5"   "5YR 4/3"   "7.5YR 4/6"
#> 
#> $Bt3
#>  [1] "10YR 3/8"   "10YR 4/10"  "7.5YR 4/13" "10YR 4/4"   "7.5YR 4/5" 
#>  [6] "10YR 4/9"   "10YR 4/3"   "10YR 3/5"   "7.5YR 4/5"  "10YR 4/5"  
#> 
#> $Cr
#>  [1] "2.5GY 6/2" "2.5G 6/3"  "2.5BG 6/3" "2.5BG 6/3" "2.5BG 7/6" "2.5G 7/3" 
#>  [7] "2.5G 6/2"  "2.5G 7/2"  "2.5G 6/2"  "2.5G 6/2" 
#> 

# preview
previewColors(parseMunsell(unlist(cols)), method = 'MDS')


# another example, this time using a larger dE00 threshold
p <- list(
  'A' = list(m = '7.5YR 3/3', thresh = 20, hues = c('10YR', '7.5YR', '5YR'))
)

# simulate
set.seed(54654)
cols <- simulateColor(method = 'dE00', n = 200, parameters = p)

# flatten
cols <- unlist(cols)

# tabulate, sort: most frequent color should be 7.5YR 3/3
sort(table(cols), decreasing = TRUE)
#> cols
#>   7.5YR 3/3   7.5YR 3/4  10YR 2.5/4  10YR 2.5/3    10YR 3/5     5YR 3/3 
#>          17           6           5           4           4           4 
#>     5YR 3/5     5YR 4/3   7.5YR 3/1   7.5YR 3/5    10YR 3/3   5YR 2.5/2 
#>           4           4           4           4           3           3 
#>     5YR 2/8     5YR 3/4     5YR 3/7     5YR 4/2   7.5YR 3/2  7.5YR 4/14 
#>           3           3           3           3           3           3 
#>    10YR 1/3  10YR 2.5/1  10YR 2.5/2  10YR 2.5/5  10YR 2.5/6  10YR 2.5/8 
#>           2           2           2           2           2           2 
#>    10YR 2/3    10YR 2/6    10YR 3/2    10YR 3/4    10YR 4/1    10YR 4/7 
#>           2           2           2           2           2           2 
#>   5YR 2.5/1   5YR 2.5/5   5YR 2.5/6     5YR 2/5    5YR 3/11     5YR 3/2 
#>           2           2           2           2           2           2 
#>     5YR 3/6     5YR 3/8     5YR 4/1     5YR 5/2     5YR 5/4 7.5YR 2.5/1 
#>           2           2           2           2           2           2 
#> 7.5YR 2.5/2 7.5YR 2.5/3 7.5YR 2.5/8   7.5YR 2/1   7.5YR 2/2   7.5YR 2/4 
#>           2           2           2           2           2           2 
#>   7.5YR 2/7   7.5YR 3/9   7.5YR 4/3   7.5YR 5/3    10YR 1/2    10YR 1/4 
#>           2           2           2           2           1           1 
#>    10YR 2/2    10YR 2/4    10YR 2/7    10YR 2/8    10YR 3/1   10YR 3/10 
#>           1           1           1           1           1           1 
#>    10YR 3/7   10YR 4/10   10YR 4/12    10YR 4/2    10YR 4/5    10YR 4/6 
#>           1           1           1           1           1           1 
#>    10YR 5/2    10YR 5/3     5YR 1/2     5YR 1/5  5YR 2.5/10   5YR 2.5/3 
#>           1           1           1           1           1           1 
#>   5YR 2.5/4   5YR 2.5/7   5YR 2.5/8    5YR 2/10     5YR 2/3     5YR 2/9 
#>           1           1           1           1           1           1 
#>     5YR 3/1     5YR 3/9    5YR 4/10    5YR 4/12     5YR 4/4     5YR 4/6 
#>           1           1           1           1           1           1 
#>     5YR 4/7     5YR 4/9     5YR 5/3     5YR 5/5   7.5YR 1/2   7.5YR 1/3 
#>           1           1           1           1           1           1 
#>   7.5YR 1/4   7.5YR 1/6 7.5YR 2.5/4 7.5YR 2.5/6 7.5YR 2.5/7   7.5YR 2/3 
#>           1           1           1           1           1           1 
#>   7.5YR 2/6  7.5YR 3/10   7.5YR 3/8  7.5YR 4/10   7.5YR 4/5   7.5YR 4/8 
#>           1           1           1           1           1           1 
#>   7.5YR 4/9   7.5YR 5/4 
#>           1           1 

# review colors
previewColors(parseMunsell(cols))


# what does a dE00 threshold look like on 3 pages of hue?
contrastChart('7.5YR 3/3', hues = c('10YR', '7.5YR', '5YR'), thresh = 20)