driftmap: Interactive driftplot and map

In tibo31/GeoXp: Interactive Exploratory Spatial Data Analysis

Interactive driftplot and map

Description

The function driftmap() creates two devices : a device with the map of coord coordinates(sf.obj) which permits to make selection of sites and a device divided into 2 rows and 2 columns which contains : (cell 1) the selected sites divided into m rows and q columns (m and q are selected with the tk window), (cell 2) a scatter plot with coordinates(sf.obj)[,2] in x-axis and the mean and median of name.var calculated for the m rows in y-axis, (cell 3) a scatter plot with the mean and median of name.var calculated for the q columns in x-axis and coordinates(sp.obj)[,1] in y-axis and (cell 4) a legend indicating the direction of the North, the variable used, etc.

Usage

driftmap(sf.obj, name.var, interpol = TRUE, nuage = TRUE, lty = 1:2, 
  cex = 0.7, carte = NULL, identify = "", 
  cex.lab = 0.8, pch = rep(16,3), col = c("lightblue3", "black", "red"), 
  xlab = "", axes = FALSE)

Arguments

sf.obj	object of class sf
name.var	a character; attribute name or column number in attribute table
interpol	if TRUE, the mean and median calculated are linearly interpoled
nuage	if TRUE, the values taken by var are also represented on right plot and on the left plot
lty	the line type for mean and median in the case of interpol=TRUE
cex	the amount by which plotting symbols on the cell 1 and in the case of nuage=TRUE cell 2 and cell 3
carte	matrix with 2 columns for drawing spatial polygonal contours : x and y coordinates of the vertices of the polygon
identify	if not NULL, the name of the variable for identifying observations on the map
cex.lab	character size of label
pch	c(16,16,16) by default, list of symbols for (1) the values of var on the left and on the right plot (2) the mean points, (3) the median points
col	c("lightblue3", "black", "red") by default, list of colors for (1) the values of var on the left and on the right plot (2) the mean points, (3) the median points
xlab	name of var printed with the legend plot
axes	a boolean with TRUE for drawing axes on the map

Details

Possibility to change the number of cells in the grid with the tk window, to interpolate the means and medians calculated (by default), to work on a rotated map. At the begining, all sites have been selected to the map : users have to deselect sites that they have choosen.

Value

In the case where user click on save results button, a vector of integer is created as a global variable in last.select object. It corresponds to the number of spatial units selected just before leaving the Tk window.

Author(s)

Thomas-Agnan C., Aragon Y., Ruiz-Gazen A., Laurent T., Robidou L.

References

Thibault Laurent, Anne Ruiz-Gazen, Christine Thomas-Agnan (2012), GeoXp: An R Package for Exploratory Spatial Data Analysis. Journal of Statistical Software, 47(2), 1-23.

See Also

angleplotmap,variocloudmap,rotation

Examples

######
# data on price indices of real estate in France
data(immob, package = "GeoXp")

# immob is a data.frame object. We have to create
# a Spatial object, by using first the longitude and latitude
require(sf)
immob.sf <- st_as_sf(immob, coords = c("longitude", "latitude"))
# optional : we add some contours that don't correspond to the spatial unit
# but are nice for mapping
midiP <- st_read(system.file("shapes/region.shp", package="GeoXp")[1])

# a simple use of driftmap
driftmap(immob.sf, "prix.vente", carte = midiP)

# ... with options
driftmap(immob.sf, "prix.vente", carte = midiP, 
  interpol = FALSE, nuage = TRUE, lty = 3:4, identify = "Nom",
  cex.lab = 0.3, xlab = "Price of sell", axes = TRUE)

## Not run:  
# data eire
require(sf)
eire <- st_read(system.file("shapes/eire.shp", package="spData")[1])

# a basic usage ...
driftmap(eire, "pale", identify = "names", nuage = TRUE)

## End(Not run)

tibo31/GeoXp documentation built on April 8, 2023, 7:50 a.m.