read_map()
download the geodetic data for a specific Origin Destination survey
and return it as an sf dataframe. It uses the cached data file if it was
previously downloaded to avoid extra networking consumption. To understand
the returned dataframe format, please reefer to the read_dictionary()
function for the same survey cohort.
It is also necessary to specify the geometry granularity wanted, be it
"municipality", "district" or "zone" level of details. Of course, not all
geometries are available for all surveys.
Arguments
- city
Character. City of reference. Defaults to "São Paulo".
- year
Numeric. Year of reference in the format
yyyy
. Defaults to1977
.- harmonize
Logical. When
FALSE
(Default), the function returns the raw data. IfTRUE
, the function returns harmonized data to the same city, across all the years.- geometry
Character. The type of spatial data to be opened. Options include
c("zone","district", "municipality")
.
Examples
library(odbr)
# return zone data from OD Surveys database as sf object at a given city and year
df <- read_map(
city = "Sao Paulo",
year = 2017,
harmonize = FALSE,
geometry = "zone"
)
#' # return district data from OD Surveys database as sf object at a given city and year
df <- read_map(
city = "Sao Paulo",
year = 2017,
harmonize = FALSE,
geometry = "district"
)
# return municipality data from OD Surveys database as sf object at a given city and year
df <- read_map(
city = "Sao Paulo",
year = 2017,
harmonize = FALSE,
geometry = "municipality"
)