cartography (version 1.4.1)

gradLinkLayer: Graduated Links Layer

Description

Plot a layer of graduated links. Links are plotted according to discrete classes of widths.

Usage

gradLinkLayer(spdf, df, spdfid = NULL, spdfids, spdfide, dfid = NULL, dfids, dfide, var, breaks = getBreaks(v = df[, var], nclass = 4, method = "quantile"), lwd = c(1, 2, 4, 6), col = "red", legend.pos = "bottomleft", legend.title.txt = var, legend.title.cex = 0.8, legend.values.cex = 0.6, legend.values.rnd = 0, legend.frame = FALSE, add = TRUE)

Arguments

spdf

SpatialLinesDataFrame; a link layer.

df

data frame with identifier(s) and a variable.

spdfid

unique identifier in spdf (spdfids, spdfide, dfids and dfide are not used).

spdfids

identifier of starting points in spdf (spdfid and dfid are not used).

spdfide

identifier of ending points in spdf (spdfid and dfid are not used).

dfid

unique identifier in df (spdfids, spdfide, dfids and dfide are not used).

dfids

identifier of starting points in df (spdfid and dfid are not used).

dfide

identifier of ending points in df (spdfid and dfid are not used).

var

name of the variable used to plot the links widths.

breaks

break values in sorted order to indicate the intervals for assigning the lines widths.

lwd

vector of widths (classes of widths).

col

color of the links.

legend.pos

position of the legend, one of "topleft", "top", "topright", "left", "right", "bottomleft", "bottom", "bottomright". If legend.pos is "n" then the legend is not plotted.

legend.title.txt

title of the legend.

legend.title.cex

size of the legend title.

legend.values.cex

size of the values in the legend.

legend.values.rnd

number of decimal places of the values displayed in the legend.

legend.frame

whether to add a frame to the legend (TRUE) or not (FALSE).

add

whether to add the layer to an existing plot (TRUE) or not (FALSE).

See Also

getLinkLayer, propLinkLayer, legendGradLines

Examples

data("nuts2006")
# Create a link layer
twincities.spdf <- getLinkLayer(spdf = nuts2.spdf, df = twincities.df[,1:2])
# Plot the links - Twin cities agreements between regions 
plot(nuts0.spdf, col = "grey60",border = "grey20")
gradLinkLayer(spdf = twincities.spdf, df = twincities.df,
              spdfids = "i", spdfide = "j",
              dfids = "i", dfide = "j",legend.pos = "topright",
              var = "fij", breaks = c(2,5,15,20,30), lwd = c(0.1,1,4,10),
              col = "#92000090", add = TRUE)