Sample ages from Goring et al PLSS data

getSampleAges.R

library(rgdal)
library(raster)

readOGR('../../data/input/shapes/')

base.rast <- raster(xmn = -71000, xmx = 2297000, ncols = 296,
                    ymn = 58000,  ymx = 1498000, nrows = 180,
                    crs = '+init=epsg:3175')

used.data <- readOGR('../../data/output//aggregated_midwest//minn.wisc.mich.clean_v1_8.shp', 
                     'minn.wisc.mich.clean_v1_8', 'minn.wisc.mich.clean_v1_8')
proj4string(used.data) <- CRS('+proj=longlat +ellps=WGS84')

used.data$year_fix <- as.numeric(as.character(used.data$year))
used.data$year_fix[used.data$year %in% "1851+"] <- 1851
used.data$year_fix[used.data$year %in% "1832-1834"] <- 1832
used.data$year_fix[used.data$year %in% "1834-1846"] <- 1834
used.data$year_fix[used.data$year %in% "1846-1851"] <- 1846
used.data$year_fix[used.data$year %in% "None"] <- 1850

age_out <- rasterize(spTransform(used.data, CRSobj = CRS('+init=epsg:3175')), 
                     base.rast, field = "year_fix")