R: assign colours to classes from classInterval object

findColours {classInt} | R Documentation

## assign colours to classes from classInterval object

### Description

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.

### Usage

    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(s)

Roger Bivand <Roger.Bivand@nhh.no

### See Also

`classIntervals`, `findInterval`, `findCols`, `colorRamp`

### 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))
    }
    if (run) {
    print(findColours(getHclustClassIntervals(h5, k=7), mypal))
    }
    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")
    }

[Package classInt version 0.4-7 Index]