getKMLcoordinates返回列表列表，而不是段列表

有一次，我绘制了一张很酷的地图，用R表示kml坐标，并将物种丰度数据叠加在上面。当我第一次编写代码时，我使用以下命令调用我的坐标列表：

---

spa示例文件包含
getKMLcoordinates
函数（maptools版本0.8-14）不需要的制表符

如果你做了一个小的修改，它会像预期的那样工作。我在添加内容的地方添加了评论：

getKMLcoordinates_01 <- function (kmlfile, ignoreAltitude = FALSE) 
{
    if (missing(kmlfile)) 
        stop("kmlfile is missing")
    kml <- paste(readLines(kmlfile, encoding = "UTF-8"), collapse = " ")
    re <- "<coordinates> *([^<]+?) *<\\/coordinates>"

    ## ++ new code
    ## remove tabs first
    kml <- gsub("\\t", "", kml)
    ##   

    mtchs <- gregexpr(re, kml)[[1]]
    coords <- list()
    for (i in 1:(length(mtchs))) {

        kmlCoords <- unlist(strsplit(gsub(re, "\\1", substr(kml, 
            mtchs[i], (mtchs[i] + attr(mtchs, "match.length")[i])), 
            perl = TRUE), split = " "))
        m <- t(as.matrix(sapply(kmlCoords, function(x) as.numeric(unlist(strsplit(x, 
            ","))), USE.NAMES = FALSE)))
        if (!ignoreAltitude && dim(m)[2] != 3) 
            message(paste("no altitude values for KML object", 
                i))
        coords <- append(coords, ifelse(ignoreAltitude, list(m[, 
            1:2]), list(m)))
    }
    coords
}

spa <- getKMLcoordinates_01("Perimeter_Track.kml")
summary(spa)
     Length Class  Mode   
[1,] 192    -none- numeric
[2,] 363    -none- numeric
[3,]  51    -none- numeric
[4,] 189    -none- numeric

getKMLcoordinates_01修复已提交至R-forge，maptools项目，版本232。请在今晚欧洲时间后试用：

install.packages("maptools", repos="http://R-Forge.R-project.org")

它处理这个问题。但是，我不知道您为什么不使用：

library(rgdal)
ogrListLayers(dsn="Perimeter_Track.kml") # to find the layer name
spa1 <- readOGR(dsn="Perimeter_Track.kml", layer="Perimeter_Track.kml")
summary(spa1)

库（rgdal）
ogrListLayers（dsn=“permiture_Track.kml”）#查找图层名称
spa1我现在把它附在问题之后。我希望它能有所帮助。我没有使用rgdal，因为MacOSX没有现成的二进制文件。我一直在努力安装这个包（请参阅我以前的.kml相关的呼救：）
  c..157.80736808..21.4323436..20.324951171875.
1                                    -157.80737
2                                      21.43234
3                                      20.32495
  c..157.80738216..21.43231443..19.36376953125.
1                                    -157.80738
2                                      21.43231
3                                      19.36377
  c..157.80533605..21.43536092..15.9990234375. c..157.8053208..21.43541138..15.9990234375.
1                                   -157.80534                                  -157.80532
2                                     21.43536                                    21.43541
3                                     15.99902                                    15.99902
  c..157.80998348..21.43706806..15.9990234375.
1                                   -157.80998
2                                     21.43707
3                                     15.99902
  c..157.80997007..21.43711106..17.441162109375.
1                                     -157.80997
2                                       21.43711
3                                       17.44116
  c..157.81074733..21.43717535..13.5958251953125.
1                                      -157.81075
2                                        21.43718
3                                        13.59583
  c..157.81071673..21.43718331..14.076416015625.
1                                     -157.81072
2                                       21.43718
3                                       14.07642

getKMLcoordinates_01 <- function (kmlfile, ignoreAltitude = FALSE) 
{
    if (missing(kmlfile)) 
        stop("kmlfile is missing")
    kml <- paste(readLines(kmlfile, encoding = "UTF-8"), collapse = " ")
    re <- "<coordinates> *([^<]+?) *<\\/coordinates>"

    ## ++ new code
    ## remove tabs first
    kml <- gsub("\\t", "", kml)
    ##   

    mtchs <- gregexpr(re, kml)[[1]]
    coords <- list()
    for (i in 1:(length(mtchs))) {

        kmlCoords <- unlist(strsplit(gsub(re, "\\1", substr(kml, 
            mtchs[i], (mtchs[i] + attr(mtchs, "match.length")[i])), 
            perl = TRUE), split = " "))
        m <- t(as.matrix(sapply(kmlCoords, function(x) as.numeric(unlist(strsplit(x, 
            ","))), USE.NAMES = FALSE)))
        if (!ignoreAltitude && dim(m)[2] != 3) 
            message(paste("no altitude values for KML object", 
                i))
        coords <- append(coords, ifelse(ignoreAltitude, list(m[, 
            1:2]), list(m)))
    }
    coords
}

spa <- getKMLcoordinates_01("Perimeter_Track.kml")
summary(spa)
     Length Class  Mode   
[1,] 192    -none- numeric
[2,] 363    -none- numeric
[3,]  51    -none- numeric
[4,] 189    -none- numeric



R version 2.15.0 Patched (2012-05-05 r59321)
Platform: x86_64-pc-mingw32/x64 (64-bit)

locale:
[1] LC_COLLATE=English_Australia.1252  LC_CTYPE=English_Australia.1252    LC_MONETARY=English_Australia.1252 LC_NUMERIC=C                      
[5] LC_TIME=English_Australia.1252    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  compiler  methods   base     

other attached packages:
[1] rgdal_0.7-8     maptools_0.8-14 lattice_0.20-6  sp_0.9-98       foreign_0.8-49 

loaded via a namespace (and not attached):
[1] grid_2.15.0  tools_2.15.0

install.packages("maptools", repos="http://R-Forge.R-project.org")

library(rgdal)
ogrListLayers(dsn="Perimeter_Track.kml") # to find the layer name
spa1 <- readOGR(dsn="Perimeter_Track.kml", layer="Perimeter_Track.kml")
summary(spa1)

o0 <- coordinates(spa1)
o1 <- lapply(o0, function(x) do.call("rbind", x))
library(maptools) # SVN revision >= 232
spa <- getKMLcoordinates('Perimeter_Track.kml', ignoreAltitude=TRUE)
all.equal(o1, spa)