data-raw/layers.R

In pbsag/swimr: Functions for Looking at Swim

# link and zone shapefiles converted to R objects

processLinks <- FALSE
processZones <- TRUE

library(maptools)
library(readr)
library(rgdal)
library(dplyr)
library(ggplot2)

options(stringsAsFactors = FALSE)

ogic <- CRS("+proj=lcc +lat_1=43 +lat_2=45.5 +lat_0=41.75 +lon_0=-120.5 +x_0=399999.9999999999 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=ft +no_defs")
wgs84 <- CRS("+proj=longlat +datum=WGS84 +no_defs")

if(processLinks) {

  # links
  links_shp <- readShapeLines(
    "data-raw/links_link.shp",
    proj4string = ogic
  ) %>%
    spTransform(., wgs84)


  links_data <- links_shp@data %>%
    tbl_df() %>%
    mutate(
      id = as.character(row_number() - 1),

      # there's a really annoying feature of R that reads in data as factors. But
      # even more annoying is the fact that the length fields in visum are written
      # as 0.159mi, which means that the numeric field gets read in as a factor.
      LENGTH = as.character(levels(LENGTH)[LENGTH])
    ) %>%
    mutate(
      LENGTH = as.numeric(gsub("[^0-9$.]", "", LENGTH))
    )

  links <- fortify(links_shp) %>%
    left_join(links_data, by = "id") %>%
    filter(!(TSYSSET %in% c("m", "n"))) %>%
    tbl_df()

  devtools::use_data(links)

}

if(processZones) {

  # zones
  zones_shp <- readShapePoly(
    "data-raw/zones_zone.shp",
    proj4string = ogic
  ) %>%
    spTransform(., wgs84)

  regions <- read_csv("data-raw/regions.csv")

  zones_shp@data <- zones_shp@data %>%
    left_join(regions) %>%
    transmute(
      NO,
      id = as.character(row_number() - 1),
      AZONE = as.numeric(as.character(NO)),
      BZONE,
      COUNTY = as.character(COUNTY),
      ALDREGION = as.character(ALDREGION),
      MPO = as.character(MPO),
      DOT_REGION,
      STATE = as.character(STATE)
    )


  zones <- fortify(zones_shp) %>% tbl_df() %>%
    left_join(zones_shp@data, by = "id")

  zones_data <- zones_shp@data

  devtools::use_data(zones, overwrite = TRUE)
  devtools::use_data(zones_data, overwrite = TRUE)
  devtools::use_data(zones_shp, overwrite = TRUE)

}