assign colours to classes from classInterval object

This helper function is a wrapper for findCols to extract classes from a "classInterval" object and assign colours from a palette created by colorRampPalette from the two or more colours given in the pal argument. It also returns two attributes for use in constructing a legend.

findColours(clI, pal, under="under", over="over", between="-", 
 digits = getOption("digits"), cutlabels=TRUE)

Arguments

clI

a "classIntervals" object

pal

a character vector of at least two colour names; colorRampPalette is used internally to create the required number of colours

under

character string value for "under" in legend if cutlabels=FALSE

over

character string value for "over" in legend if cutlabels=FALSE

between

character string value for "between" in legend if cutlabels=FALSE

digits

minimal number of significant digits in legend

cutlabels

use cut-style labels in legend

Value

a character vector of colours with attributes: "table", a named frequency table; "palette", a character vector of colours corresponding to the specified breaks.

Author

Roger Bivand <Roger.Bivand@nhh.no

Examples

if (!require("spData", quietly=TRUE)) {
  message("spData package needed for examples")
  run <- FALSE
} else {
  run <- TRUE
}
if (run) {
data(jenks71, package="spData")
mypal <- c("wheat1", "red3")
h5 <- classIntervals(jenks71$jenks71, n=5, style="hclust", method="complete")
print(findColours(h5, mypal))
}
#>   [1] "#FFE7BA" "#E6735D" "#E6735D" "#F2AD8B" "#E6735D" "#E6735D" "#E6735D"
#>   [8] "#E6735D" "#D9392E" "#CD0000" "#D9392E" "#D9392E" "#E6735D" "#E6735D"
#>  [15] "#F2AD8B" "#E6735D" "#E6735D" "#E6735D" "#E6735D" "#D9392E" "#F2AD8B"
#>  [22] "#E6735D" "#F2AD8B" "#F2AD8B" "#E6735D" "#F2AD8B" "#F2AD8B" "#F2AD8B"
#>  [29] "#F2AD8B" "#E6735D" "#F2AD8B" "#FFE7BA" "#F2AD8B" "#F2AD8B" "#F2AD8B"
#>  [36] "#F2AD8B" "#FFE7BA" "#FFE7BA" "#F2AD8B" "#F2AD8B" "#FFE7BA" "#F2AD8B"
#>  [43] "#F2AD8B" "#FFE7BA" "#F2AD8B" "#F2AD8B" "#FFE7BA" "#F2AD8B" "#FFE7BA"
#>  [50] "#FFE7BA" "#F2AD8B" "#F2AD8B" "#FFE7BA" "#F2AD8B" "#F2AD8B" "#FFE7BA"
#>  [57] "#F2AD8B" "#F2AD8B" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA"
#>  [64] "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA"
#>  [71] "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA"
#>  [78] "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA"
#>  [85] "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA"
#>  [92] "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA"
#>  [99] "#FFE7BA" "#FFE7BA" "#FFE7BA" "#FFE7BA"
#> attr(,"palette")
#> [1] "#FFE7BA" "#F2AD8B" "#E6735D" "#D9392E" "#CD0000"
#> attr(,"table")
#>   [15.57,54.81)  [54.81,74.405) [74.405,105.95)  [105.95,143.4)   [143.4,155.3] 
#>              55              27              15               4               1 
if (run) {
print(findColours(getHclustClassIntervals(h5, k=7), mypal))
}
#>   [1] "#F6C09B" "#E6735D" "#E6735D" "#EE9A7C" "#E6735D" "#E6735D" "#E6735D"
#>   [8] "#DD4D3E" "#D5261F" "#CD0000" "#D5261F" "#D5261F" "#DD4D3E" "#E6735D"
#>  [15] "#EE9A7C" "#DD4D3E" "#E6735D" "#E6735D" "#E6735D" "#D5261F" "#EE9A7C"
#>  [22] "#E6735D" "#EE9A7C" "#EE9A7C" "#E6735D" "#EE9A7C" "#EE9A7C" "#EE9A7C"
#>  [29] "#EE9A7C" "#DD4D3E" "#EE9A7C" "#F6C09B" "#EE9A7C" "#EE9A7C" "#EE9A7C"
#>  [36] "#EE9A7C" "#F6C09B" "#F6C09B" "#EE9A7C" "#EE9A7C" "#F6C09B" "#EE9A7C"
#>  [43] "#EE9A7C" "#F6C09B" "#EE9A7C" "#EE9A7C" "#F6C09B" "#EE9A7C" "#F6C09B"
#>  [50] "#F6C09B" "#EE9A7C" "#EE9A7C" "#F6C09B" "#EE9A7C" "#EE9A7C" "#F6C09B"
#>  [57] "#EE9A7C" "#EE9A7C" "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B"
#>  [64] "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B"
#>  [71] "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B"
#>  [78] "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B" "#F6C09B"
#>  [85] "#F6C09B" "#F6C09B" "#F6C09B" "#FFE7BA" "#F6C09B" "#FFE7BA" "#FFE7BA"
#>  [92] "#F6C09B" "#F6C09B" "#FFE7BA" "#FFE7BA" "#FFE7BA" "#F6C09B" "#FFE7BA"
#>  [99] "#FFE7BA" "#FFE7BA" "#FFE7BA" "#F6C09B"
#> attr(,"palette")
#> [1] "#FFE7BA" "#F6C09B" "#EE9A7C" "#E6735D" "#DD4D3E" "#D5261F" "#CD0000"
#> attr(,"table")
#>  [15.57,29.84)  [29.84,54.81) [54.81,74.405) [74.405,90.16) [90.16,105.95) 
#>             10             45             27             11              4 
#> [105.95,143.4)  [143.4,155.3] 
#>              4              1 
if (run) {
h5Colours <- findColours(h5, mypal)
plot(h5, mypal, main="Complete hierarchical clustering")
legend(c(95, 155), c(0.12, 0.4), fill=attr(h5Colours, "palette"),
 legend=names(attr(h5Colours, "table")), bg="white")
}

if (run) {
h5tab <- attr(h5Colours, "table")
legtext <- paste(names(h5tab), " (", h5tab, ")", sep="")
plot(h5, mypal, main="Complete hierarchical clustering (with counts)")
legend(c(95, 165), c(0.12, 0.4), fill=attr(h5Colours, "palette"),
 legend=legtext, bg="white")
}