draw_subcatchments_OCN {OCNet}

Draw subcatchment map from an Optimal Channel Network

Description

Function that draws a map of subcatchments generated by the aggregation process on the OCN. If theme is NULL, colormap is such that neighbouring subcatchments have distinguished colors. If theme is specified, colors reflect the values of theme across subcatchments, in analogy with draw_thematic_OCN.

Usage

draw_subcatchments_OCN(OCN, theme = NULL, drawRiver = TRUE,
 colPalette = NULL, colLevels = NULL, riverColor = NULL, addLegend = NULL, 
 min_lwd = 0.5, max_lwd = 5, add = FALSE, args_imagePlot = list(), ...)

Arguments

OCN

A river object as produced by aggregate_OCN.

theme

Vector (of length OCN$SC$Nnodes expressing the spatial field of interest.

drawRiver

Logical. If TRUE, draw the OCN on top of the subcatchment map.

colPalette

Color palette used. colPalette accepts both functions creating color palettes and vectors of colors. In the latter case, length(colPalette) must be greater than the number of color levels. If theme = NULL, default is c("#009900", "#FFFF00", "#FF9900", "#FF0000", "#FF00FF", "#9900CC", "#555555", "#BBBBBB"). Only the first n colors are used, where n is the number of different colors needed (calculated via a greedy coloring algorithm). colPalette accepts both functions creating color palettes and vectors of colors (see examples); in the latter case, the length of the vector cannot be lower than n (n cannot be predicted a priori, but generally 6 colors should suffice). If theme != NULL, default is colorRampPalette(c("yellow","red","black")).

colLevels

Number of colors in the palette (only effective if theme is not null). colLevels must be a vector of the form c(minval, maxval) or c(minval, maxval, N_levels). The vector of breakpoints used to attribute theme values to a given color is then defined as seq(minval, maxval, N_levels). Default is minval = min(theme[!(is.nan(theme))]), maxval = max(theme[!(is.nan(theme))]), N_levels = 1000.

riverColor

Color used to display the OCN (only effective if drawRiver = TRUE).

addLegend

Logical. State if a legend should be displayed (only active if theme is not null.

min_lwd, max_lwd

Minimum and maximum values of line width used to display the OCN (actual line width is proportional to the square root of drainage area).

add

Logical. If TRUE, add to an already existing plot. Taken as FALSE (with a warning if a different value is supplied) if no graphics device is open.

args_imagePlot

Only effective if addLegend = TRUE. List of arguments passed to imagePlot for drawing a continuous legend. For example, argument smallplot can be used to specify the plot coordinates for the legend.

...

Further arguments to be passed to image. Default plot options are as in draw_thematic_OCN.

Value

No output is returned.

See Also

draw_thematic_OCN

Examples

# 1a) aggregate a 20x20 OCN , use thrA = 5 pixels
# and draw subcatchments with default color palette
OCN <- aggregate_OCN(landscape_OCN(OCN_20), thrA = 5)
draw_subcatchments_OCN(OCN, drawRiver = TRUE)

# 1b) same as above, but define color palette with a function
draw_subcatchments_OCN(OCN, drawRiver = TRUE, colPalette = rainbow)

# 1c) same as above, but define color palette with a vector of colors
draw_subcatchments_OCN(OCN, drawRiver = TRUE, colPalette = hcl.colors(6, "Dark 3"))

# 2) Display theme at subcatchment level
draw_subcatchments_OCN(OCN, theme = OCN$AG$A)