showColors function

Show colors from a vector or list

showColors(
  x,
  labelCells = NULL,
  transpose = FALSE,
  srtCellnote = NULL,
  adjustMargins = TRUE,
  makeUnique = FALSE,
  doPlot = TRUE,
  ...
)

Arguments

• x: one of these input types:

  • character vector of colors
  • function to produce colors, for example circlize::colorRamp2()
  • list with any combination of character or function

• labelCells: logical whether to label colors atop the color itself. If NULL (default) it will only display labels with 40 or fewer items on either axis.

• transpose: logical whether to transpose the colors to display top-to-bottom, instead of left-to-right.

• srtCellnote: numeric angle to rotate text when labelCells=TRUE. When set to NULL, labels are vertical srtCellnote=90 when transpose=FALSE and horizontal srtCellnote=0 when transpose=TRUE.

• adjustMargins: logical indicating whether to call adjustAxisLabelMargins() to adjust the x- and y-axis label margins to accomodate the label size.

  • Note when an axis is hidden by using xaxt="n" or xaxt="n", the respective margin will not be adjusted.
  • The arguments in ... take precedence over graphics::par(), when deciding whether to adjust margins. However if xaxt="s" and graphics::par("xaxt"="n") the margin will be adjusted but not displayed. In this way the axes can be adjusted without displaying the labels, so the labels can be rendered later if needed.

• makeUnique: logical indicating whether to display only the first unique color. When x is supplied as a list this operation will display the first unique color for each list element. Also, when x is a list, just to be fancy, makeUnique

  is recycled to length(x) so certain list elements can display unique values, while others display all values.

• doPlot: logical indicating whether to produce a visual plot. Note this function returns the color matrix invisibly.

• ...: additional parameters are passed to imageByColors().

Returns

invisible color matrix used by imageByColors(). When the input x is empty, or cannot be converted to colors when x contains a function, the output returns NULL.

Details

This function simply displays colors for review, using imageByColors() to display colors and labels across the plot space.

When supplied a list, each row in imageByColors() represents an entry in the list. Nothing fancy.

Examples

x <- color2gradient(list(Reds=c("red"), Blues=c("blue")), n=c(4,7));
showColors(x);

showColors(getColorRamp("firebrick3"))

if (requireNamespace("RColorBrewer", quietly=TRUE)) {
   RColorBrewer_namelist <- rownames(RColorBrewer::brewer.pal.info);
   y <- lapply(nameVector(RColorBrewer_namelist), function(i){
      n <- RColorBrewer::brewer.pal.info[i, "maxcolors"]
      j <- RColorBrewer::brewer.pal(n, i);
      nameVector(j, seq_along(j));
   });
   showColors(y, cexCellnote=0.6, cex.axis=0.7, main="Brewer Colors");
}
if (requireNamespace("viridisLite", quietly=TRUE)) {
   # given one function name it will display discrete colors
   showColors(viridisLite::viridis)
   # a list of functions will show each function output
   showColors(list(viridis=viridisLite::viridis,
      inferno=viridisLite::inferno))

   # grab the full viridis color map
   z <- rgb2col(viridisLite::viridis.map[,c("R","G","B")]);
   # split the colors into a list
   viridis_names <- c(A="magma",
      B="inferno",
      C="plasma",
      D="viridis",
      E="cividis",
      F="rocket",
      G="mako",
      H="turbo")
   y <- split(z,
      paste0(viridisLite::viridis.map$opt, ": ",
      viridis_names[viridisLite::viridis.map$opt]));
   showColors(y, labelCells=TRUE, xaxt="n", main="viridis.map colors");
}

# demonstrate makeUnique=TRUE
j1 <- getColorRamp("rainbow", n=7);
names(j1) <- seq_along(j1);
j2 <- rep(j1, each=3);
names(j2) <- makeNames(names(j2), suffix="_rep");
j2
showColors(list(
   j1=j1,
   j2=j2,
   j3=j2),
   makeUnique=c(FALSE, FALSE, TRUE))

See Also

Other jam plot functions: adjustAxisLabelMargins(), coordPresets(), decideMfrow(), drawLabels(), getPlotAspect(), groupedAxis(), imageByColors(), imageDefault(), minorLogTicksAxis(), nullPlot(), plotPolygonDensity(), plotRidges(), plotSmoothScatter(), shadowText(), shadowText_options(), sqrtAxis(), usrBox()

Other jam color functions: alpha2col(), applyCLrange(), col2alpha(), col2hcl(), col2hsl(), col2hsv(), color2gradient(), fixYellow(), fixYellowHue(), getColorRamp(), hcl2col(), hsl2col(), hsv2col(), isColor(), kable_coloring(), makeColorDarker(), rainbow2(), rgb2col(), setCLranges(), setTextContrastColor(), unalpha(), warpRamp()