In bniebuhr/howtoRpackage: Tips to create R packages

library(plyr)

Albers.crs <-CRS("+proj=aea +lat_1=29.3 +lat_2=45.3 +lat_0=23 +lon_0=-96 +x_0=0 +y_0=0 +datum=NAD83 +units=m +no_defs +ellps=GRS80 +towgs84=0,0,0")

juveniles <- read.csv("subsetGPSlocs.csv", header=T)

juveniles$NewDate <- as.POSIXct(juveniles$NewDate, format="%Y-%m-%d %H:%M:%S", tz="EST")
juveniles$SeasonYear <- NULL
juveniles$SeasonYear[juveniles$NewDate > "2018-01-01 00:00:00" &
  juveniles$NewDate < "2018-08-01 00:00:00"] <- "Spring18"
juveniles$SeasonYear[juveniles$NewDate > "2019-01-01 00:00:00" &
  juveniles$NewDate < "2019-08-01 00:00:00"] <- "Spring19"
juveniles$SeasonYear[juveniles$NewDate > "2020-01-01 00:00:00" &
  juveniles$NewDate < "2020-08-11 00:00:00"] <- "Spring20"
juveniles$SeasonYear[juveniles$NewDate > "2018-07-31 23:59:00" &
  juveniles$NewDate < "2018-12-31 23:59:00"] <- "Fall18"
juveniles$SeasonYear[juveniles$NewDate > "2019-07-31 23:59:00" &
  juveniles$NewDate < "2019-12-31 23:59:00"] <- "Fall19"

juveniles$SeasonYearBurst <- c(paste(juveniles$individual.local.identifier,juveniles$SeasonYear,sep="_"))
juveniles$SeasonYearBurst <- as.factor(juveniles$SeasonYearBurst)

juv18to20<-data.frame(x = juveniles$x, y = juveniles$y)

juv18to20.spdf <- SpatialPointsDataFrame(coords= juv18to20, data = juveniles, proj4string = Albers.crs)
# writeOGR(juv18to20.spdf, dsn = ".", layer="PA_juveniles_all", driver = "ESRI Shapefile")
# write.csv(juveniles,"juvenileGPSlocs.csv")


fixrate <- function(x){
   dates=range(x$NewDate)
   print(dates)
   days=as.numeric(round(diff(range(x$NewDate)), digits=0))
   print(days)
   sched=as.numeric(round(median(diff(x$NewDate)), digits=0))
   print(sched)
   expected= as.numeric(days)*round(1440/(as.numeric(sched)), digits=0)#1440 minutes in a day
   print(expected)
   success <- nrow(x)
   print(success)
   percentfix <- round(success/expected*100)
   print(paste(percentfix,"%", sep=" "))
}


fix_deer <- ddply(juveniles, .(individual.local.identifier), fixrate)