Rstudio中安装package出现的问题及解决

# set a CRAN mirror
local({r <- getOption(“repos”)
r[“CRAN”] <- “Http://mirrors.tuna.tsinghua.edu.cn/CRAN/”
options(repos=r)}

install.packages("mirt")
WARNING: Rtools is required to build R packages but is not currently installed. Please download and install the appropriate version of Rtools before proceeding:

https://cran.rstudio.com/bin/windows/Rtools/
Installing package into ‘C:/Users/likailei/Documents/R/win-library/3.6'
(as ‘lib' is unspecified)
Warning in install.packages :
 unable to access index for repository https://cran.rstudio.com/src/contrib:
 cannot open URL 'https://cran.rstudio.com/src/contrib/PACKAGES'
Warning in install.packages :
 package ‘mirt' is not available (for R version 3.6.0)
Warning in install.packages :
 unable to access index for repository https://cran.rstudio.com/bin/windows/contrib/3.6:
 cannot open URL 'https://cran.rstudio.com/bin/windows/contrib/3.6/PACKAGES'

install.packages("mirt")
WARNING: Rtools is required to build R packages but is not currently installed. Please download and install the appropriate version of Rtools before proceeding:

https://cran.rstudio.com/bin/windows/Rtools/
Installing package into ‘C:/Users/likailei/Documents/R/win-library/3.6'
(as ‘lib' is unspecified)
also installing the dependencies ‘permute', ‘GPArotation', ‘Rcpp', ‘vegan', ‘Deriv', ‘dcurver', ‘RcppArmadillo'

trying URL 'https://mirrors.tongji.edu.cn/CRAN/bin/windows/contrib/3.6/permute_0.9-5.zip'
Content type 'application/zip' length 505181 bytes (493 KB)
downloaded 493 KB

trying URL 'https://mirrors.tongji.edu.cn/CRAN/bin/windows/contrib/3.6/GPArotation_2014.11-1.zip'
Content type 'application/zip' length 162104 bytes (158 KB)
downloaded 158 KB

trying URL 'https://mirrors.tongji.edu.cn/CRAN/bin/windows/contrib/3.6/Rcpp_1.0.1.zip'
Content type 'application/zip' length 4494896 bytes (4.3 MB)
downloaded 4.3 MB

trying URL 'https://mirrors.tongji.edu.cn/CRAN/bin/windows/contrib/3.6/vegan_2.5-5.zip'
Content type 'application/zip' length 3861520 bytes (3.7 MB)
downloaded 3.7 MB

trying URL 'https://mirrors.tongji.edu.cn/CRAN/bin/windows/contrib/3.6/Deriv_3.8.5.zip'
Content type 'application/zip' length 133828 bytes (130 KB)
downloaded 130 KB

trying URL 'https://mirrors.tongji.edu.cn/CRAN/bin/windows/contrib/3.6/dcurver_0.9.1.zip'
Content type 'application/zip' length 639915 bytes (624 KB)
downloaded 624 KB

trying URL 'https://mirrors.tongji.edu.cn/CRAN/bin/windows/contrib/3.6/RcppArmadillo_0.9.400.3.0.zip'
Content type 'application/zip' length 2276463 bytes (2.2 MB)
downloaded 2.2 MB

trying URL 'https://mirrors.tongji.edu.cn/CRAN/bin/windows/contrib/3.6/mirt_1.30.zip'
Content type 'application/zip' length 2572772 bytes (2.5 MB)
downloaded 2.5 MB

package ‘permute' successfully unpacked and MD5 sums checked
package ‘GPArotation' successfully unpacked and MD5 sums checked
package ‘Rcpp' successfully unpacked and MD5 sums checked
package ‘vegan' successfully unpacked and MD5 sums checked
package ‘Deriv' successfully unpacked and MD5 sums checked
package ‘dcurver' successfully unpacked and MD5 sums checked
package ‘RcppArmadillo' successfully unpacked and MD5 sums checked
package ‘mirt' successfully unpacked and MD5 sums checked