rCarto (version 0.8)

mapCircles: Proportional Circles

Description

This function represents a variable through a proportional circles map. The areas of the circles are proportional to values of a numeric variable.

Usage

mapCircles(shpFile, shpId, df, dfId, var,
          fixedNorm = FALSE, shareOfCircles = 0.02, 
          radiusMax = 0.5, valueMax = max(df[, var], na.rm = TRUE), 
          lgdRnd = 0, posLeg = "bottomleft", 
          circleCol = "#FD8D3C", baseCol = "#FFEDA0", 
          title = var, legend = var, author = "author", sources = "sources", 
          scalebar = FALSE, scalebarSize, scalebarText, 
          northArrow = FALSE, northArrowSize, 
          width = NULL, height = NULL, txtCex = NULL)

Arguments

shpFile

Path to a polygon shapefile.

shpId

Unique identifier of the shapefile. It must correspond to dfId.

df

Data frame that contains the variable to be mapped.

dfId

Unique identifier of the data frame. It must correspond to shpId.

var

Name of the positive numeric variable to be mapped.

fixedNorm

FALSE (default) : the sum of the surfaces occupied by circles is proportional to the size of the map and is declared by the shareOfCircles argument, radiusMax and valueMax are not used. TRUE

shareOfCircles

Share of the surface of the map occupied by circles (0.02 is 2%).

radiusMax

Size (in cm) of the radius of the biggest circle.

valueMax

Value used to normalize the size of the largest circle (in variable units).

lgdRnd

Rounding of the values of the variable presented in the legend.

posLeg

Position of the legend (top, bottom, left, right, center, topleft, topright, bottomleft or bottomright).

circleCol

Color of the circles.

baseCol

Color of the base map.

title

Title of the map.

legend

Title of the legend.

author

Two lines (author and sources) at the bottom of the map are available to display additional information. It is recommended to display the name of the author and the sources of the data and the base map.

sources

Two lines (author and sources) at the bottom of the map are available to display additional information. It is recommended to display the name of the author and the sources of the data and the base map.

scalebar

FALSE (default): don't draw a scale bar. TRUE : draws a scale bar. The choice of the scale bar location is interactive.

scalebarSize

Size of the scale bar in map units.

scalebarText

Text of the scale bar.

northArrow

FALSE (default) : don't draw a North arrow. TRUE : draws a North arrow. The choice of the North arrow location is interactive.

northArrowSize

Size of the North arrow in map units.

width

Width of the map in cm.

height

Height of the map in cm.

txtCex

Size of the texts.

Value

• A proportionnal circle map is displayed in the graphic window. You can export the map in raster or vector format (pdf).

Details

The circles are centered on the centroids of the polygons. Only the five first arguments are compulsory.

See Also

ll{ rCarto-package rCarto package mapCircles proportional circles mapCirclesChoro proportional circles colored by a discretized quantitative variable mapCirclesTypo proportional circles colored by the modalities of a qualitative variable mapChoropleth choropleth mapChoroTypo typology mtq data commune shapefile }

Examples

library(rCarto)
data(mtq)
# minimal example
mapCircles(shpFile=file.path(path.package("rCarto"), "shapes/COMMUNE"),
           shpId="INSEE_COM",df=mtq,dfId="ID",var="P09_POP", )

# detailed example
mapCircles(shpFile=file.path(path.package("rCarto"), "shapes/COMMUNE"),
           shpId="INSEE_COM",df=mtq,dfId="ID",var="P09_POP",
           shareOfCircle=0.1,
           lgdRnd=0,circleCol="Red",
           title="Population distribution in Martinique",
           legend="Total resident
population in 2009",
           author=Sys.getenv("USERNAME"),
           sources="data : INSEE,2009; basemap : IGN, 2012")