##读取含有地名、经纬度的excel文件
city_wmat <- read.table("clipboard",header=TRUE)
genW <- function (coords, labels)
   {
    W <- as.matrix(dist(coords))
    colnames(W) <- labels
    rownames(W) <- labels
    W[which(W == Inf)] <- 0
    return(W)
    }
##注意这时的距离单位是：百公里
##距离倒数
genW <- function (coords, labels)
    {
    W <- 1/ as.matrix(dist(coords))
    colnames(W) <- labels
    rownames(W) <- labels
    W[which(W == Inf)] <- 0
    return(W)
    }

wmat <- genW(cbind(city_wmat$weidu,city_wmat$jingdu),city_wmat$cityname)