问题
Im trying to calculate the nearest distance to a point. Therefore I create two df's
Create list 1
long <- c(52.070498, 52.370216, 52.632381, 53.201233, 51.813298, 51.92442, 52.266075, 53.219383, 52.960561, 52.367027, 51.571915, 52.516775, 51.441642, 52.221537, 52.090737, 51.985103, 51.560596)
lat <- c(4.3007, 4.895168,4.753375, 5.799913, 4.690093, 4.477733, 6.155217, 6.566502, 5.920522, 6.668492, 4.768323, 6.083022, 5.469722, 6.893662, 5.12142, 5.89873, 5.091914)
stad <- c("Den Haag", "Amsterdam", "Alkmaar", "Leeuwarden", "Dordrecht", "Rotterdam", "Deventer", "Groningen", "Heerenveen", "Almelo", "Breda", "Zwolle", "Eindhoven", "Enschede", "Utrecht", "Arnhem", "Tilburg")
list1 <- data.frame(longitude=long, latitude=lat, stad)
Create list 2
long <- c("51.476364", "52.12379", "52.456954", "51.543197", "52.307687", "53.250184", "52.640436", "53.397875", "52.491691", "52.109272", "52.121092", "52.882946", "52.518537", "53.201233", "52.711559", "52.066719", "53.405366", "52.433881", "53.128855", "51.641078", "53.189226", "52.716927", "51.453667", "51.233528", "51.529207", "51.980632", "51.429248", "51.92442", "51.441642", "50.851368")
lat <- c("6.180948", "4.438598", "4.606014", "6.087664", "4.767424", "4.951427", "4.998517", "5.346679", "4.593325", "5.180968", "5.285347", "5.360707", "5.471422", "5.799913", "5.864559", "5.894033", "6.212048", "6.232888", "6.587567", "5.619458", "7.162511", "5.737644", "3.570912", "3.830322", "3.89688", "4.134185", "4.304708", "4.477733", "5.469722", "5.690973")
stad <- c("Valkenburg", "Voorschoten", "Ijmuiden", "De kooy", "Schiphol", "Vlieland", "Berkhout", "Hoorn (terschelling)", "Wijk aan zee", "De Bilt", "Soesterberg", "Stavoren", "Lelystad", "Leeuwarden", "Marknesse", "Deelen", "Lauwersoog", "Heino", "Eelde", "Hupsel", "Nieuwe beerta", "Twente", "Vlissingen", "Westdorpe", "Wilhelminadorp", "Hoek van Holland", "Woensdrecht", "Rotterdam", "Eindhoven", "Maastricht")
list2 <- data.frame(longitude=long, latitude=lat , stad)
But then when I do:
library(geosphere)
mat <- distm(list1[,c('longitude','latitude')], list2[,c('longitude','latitude')], fun=distVincentyEllipsoid)
I get:
Error in .pointsToMatrix(x) : longitude > 360
list1$locality <- list2$stad[apply(mat, 1, which.min)]
回答1:
Apparently, the problem is that list2 contains factors instead of floats in longitude and latitude columns.
It seems to work once you convert factor values to numerical values specified by labels:
list2$longitude.fix <- as.numeric(levels(list2$longitude))[list2$longitude]
list2$latitude.fix <- as.numeric(levels(list2$latitude))[list2$latitude]
distm(list1[,c('longitude','latitude')], list2[,c('longitude.fix','latitude.fix')], fun=distVincentyEllipsoid)
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] …
[1,] 218106.26 16356.00 54584.86 206073.80 57935.42 149371.56 99767.31 187239.60 …
[2,] 173280.56 57416.26 33391.75 160587.51 15737.20 97796.65 32074.61 124403.87 …
[3,] 203303.45 66306.56 25384.63 190634.04 36054.40 71943.23 27123.09 107285.19 …
[4,] 195563.08 192179.83 155688.71 186323.20 151151.41 93985.73 108243.57 54651.40 …
[5,] 169040.53 44278.35 72020.04 157421.51 55511.66 161989.79 97883.85 190131.21 …
…
回答2:
In your second list you have Strings.
long <- as.numeric(c("51.476364", "52.12379", "52.456954", "51.543197", "52.307687", "53.250184", "52.640436", "53.397875", "52.491691", "52.109272", "52.121092", "52.882946", "52.518537", "53.201233", "52.711559", "52.066719", "53.405366", "52.433881", "53.128855", "51.641078", "53.189226", "52.716927", "51.453667", "51.233528", "51.529207", "51.980632", "51.429248", "51.92442", "51.441642", "50.851368"))
lat <- as.numeric(c("6.180948", "4.438598", "4.606014", "6.087664", "4.767424", "4.951427", "4.998517", "5.346679", "4.593325", "5.180968", "5.285347", "5.360707", "5.471422", "5.799913", "5.864559", "5.894033", "6.212048", "6.232888", "6.587567", "5.619458", "7.162511", "5.737644", "3.570912", "3.830322", "3.89688", "4.134185", "4.304708", "4.477733", "5.469722", "5.690973"))
stad <- c("Valkenburg", "Voorschoten", "Ijmuiden", "De kooy", "Schiphol", "Vlieland", "Berkhout", "Hoorn (terschelling)", "Wijk aan zee", "De Bilt", "Soesterberg", "Stavoren", "Lelystad", "Leeuwarden", "Marknesse", "Deelen", "Lauwersoog", "Heino", "Eelde", "Hupsel", "Nieuwe beerta", "Twente", "Vlissingen", "Westdorpe", "Wilhelminadorp", "Hoek van Holland", "Woensdrecht", "Rotterdam", "Eindhoven", "Maastricht")
list2 <- data.frame(longitude=long, latitude=lat , star)
or you just remove the quotes
来源：https://stackoverflow.com/questions/34576333/error-in-pointstomatrixx-longitude-360-with-calculating-distance