001、R语言中安装maptools出现如下问题: > install.packages("maptools") 将程序包安装入‘C:/Users/liujiaxin/AppData/Local/R/win-library/4.3’ (因为‘lib’没有被指定) Warningininstall.packages :package ‘maptools’isnot availableforthisversion of RA version ofthispackageforyour version of R might...