如何将gpclibPermit()转为TRUE

Question

当我跑步时gpclibPermit(),我得到了答案FALSE.我怎样才能改变它TRUE？

Answer 1

我自己也在努力解决这个gpclibPermit问题.你没有提供一个可重复的例子,但我猜你有这样一个sesion:

library(maptools)
Checking rgeos availability: FALSE
Note: when rgeos is not available, polygon geometry computations in maptools depend 
    on gpclib, which has a restricted licence. It is disabled by default;
to enable gpclib, type gpclibPermit()
> gpclibPermitStatus()
[1] FALSE
> gpclibPermit()
[1] FALSE
> gpclibPermitStatus()
[1] FALSE

在这一点上它有助于看什么gpclibPermit和gpclibPermitStatus实际上做:

> gpclibPermit
function ()  
{
if ("gpclib" %in% .packages(all.available = TRUE)) 
    assign("gpclib", TRUE, envir = .MAPTOOLS_CACHE)
if (gpclibPermitStatus()) 
    warning("support for gpclib will be withdrawn from maptools at the next major release")
gpclibPermitStatus()
}
<environment: namespace:maptools>
> gpclibPermitStatus
function () 
    get("gpclib", envir = .MAPTOOLS_CACHE)
<environment: namespace:maptools>

也就是说,除非安装了软件包,否则不能授予maptools使用权限. gpclibgpclib

install.packages("gpclib")
library(maptools)
Loading required package: sp
Checking rgeos availability: FALSE
Note: when rgeos is not available, polygon geometry computations in maptools depend on gpclib,  which has a restricted licence. It is disabled by default; to enable gpclib, type gpclibPermit()

> gpclibPermit()
[1] TRUE
Warning message:
In gpclibPermit() :
support for gpclib will be withdrawn from maptools at the next major release
> gpclibPermitStatus()
[1] TRUE

Answer 2

我自己有这个问题,发现最容易安装rgeos,并确保在连接之前已连接maptools

library(ggplot2)
library(rgeos)
library(maptools)