c++ - 加载 Rcpp 并运行示例代码

Question

我是 R 的新手，我对 Rcpp 有疑问。从这个 URL http://www.r-bloggers.com/installing-rcpp-on-windows-7-for-r-and-c-integration/我已按照所有步骤安装 Rcpp。我还安装并加载了 RcppClassic 和 Rinside。当我尝试运行建议的代码时:

# install packages
install.packages(c("Rcpp", "rbenchmark", "inline", "Runit"))

# load main two packages
library(Rcpp)
library(inline)

# do something with Rcpp to quickly check that it works
body <- '
NumericVector xx(x);
return wrap( std::accumulate( xx.begin(), xx.end(), 0.0));'

add <- cxxfunction(signature(x = "numeric"), body, plugin = "Rcpp")

x <- 1
y <- 2
res <- add(c(x, y))
res
#[1] 3

我收到以下消息:

package ‘Rcpp’ successfully unpacked and MD5 sums checked 
Warning: cannot remove prior installation of package ‘Rcpp’ package
‘rbenchmark’ successfully unpacked and MD5 sums checked package
‘inline’ successfully unpacked and MD5 sums checked 
package ‘RUnit’ successfully unpacked and MD5 sums checked

 The downloaded binary packages are in
         C:\Users\Ron\AppData\Local\Temp\RtmpE3jrvo\downloaded_packages 

Error in library(Rcpp) : there is no package called ‘Rcpp’

同样很奇怪的是，如果我尝试使用 UI 并选择加载 Rcpp，它不会显示为一个选项。

Answer 1

你忽略了这一点:

Warning: cannot remove prior installation of package ‘Rcpp’

停止所有 R session 。重新开始，不要加载 Rcpp，然后尝试安装/升级它。

您使用的操作系统有点受限，因为您无法删除正在使用的共享库。