This package provides functions to compute the potential model as defined by Stewart (1941). Several options are available to customize the model, for example it is possible to fine-tune the distance friction functions or to use custom distance matrices. Some computations are parallelized to improve their efficiency.
You can install the released version of potential from
CRAN with:
install.packages("potential")You can install the development version of potential from GitHub with:
# install.packages("remotes")remotes::install_github("riatelab/potential")library(mapsf)
library(potential)
# Display the spatial interaction function
plot_inter(fun="e", span=75000, beta=2, limit=250000)
# create a regular gridy<- create_grid(x=n3_poly, res=20000)
# compute potentialspot<- mcpotential(
x=n3_pt, y=y,
var="POP19",
fun="e", span=75000,
beta=2, limit=250000, ncl=2
)
# Define potential according to the maximum valuey$pot<-pot/ max(pot) *100# create equipotential areasbks<- seq(0, 100, length.out=11)
equipot<- equipotential(y, var="pot", breaks=bks, mask=n3_poly)
# map potentials
mf_map(x=equipot, var="min", type="choro", breaks=bks, pal= hcl.colors(10, 'Teal'),
border="#121725", leg_val_rnd=0,
lwd=.2, leg_pos="topright", leg_title="Potential Intensity")
mf_title(txt="Potentials of Population")
mf_credits(txt="© EuroGeographics for the administrative boundaries and © Eurostat for data")
This package provides access to the revamped potential-related functions
initially offered by
SpatialPosition.
Stewart, John Q. 1941. “An Inverse Distance Variation for Certain Social Influences.” Science 93 (2404): 89–90. https://doi.org/10.1126/science.93.2404.89.