在Ubuntu安裝R語言的rvest套件。
rvest是R語言的一個套件，安裝的方式是在R執行
install.packages("rvest")
之前在Windows的環境下可以應該是直接安裝就可以了，
但換成在Ubuntu，卻無法直接安裝。執行時會出現一些錯誤訊息。
錯誤訊息1
————————- ANTICONF ERROR —————————
Configuration failed because libcurl was not found. Try installing:
* deb: libcurl4-openssl-dev (Debian, Ubuntu, etc)
* rpm: libcurl-devel (Fedora, CentOS, RHEL)
* csw: libcurl_dev (Solaris)
If libcurl is already installed, check that ‘pkg-config’ is in your
PATH and PKG_CONFIG_PATH contains a libcurl.pc file. If pkg-config
is unavailable you can set INCLUDE_DIR and LIB_DIR manually via:R CMD INSTALL –configure-vars=‘INCLUDE_DIR=… LIB_DIR=…’
解決方式：依指示到terminal安裝libcurl4-openssl-dev
sudo apt-get update
sudo apt-get install libcurl4-openssl-dev
錯誤訊息2
————————- ANTICONF ERROR —————————
Configuration failed because openssl was not found. Try installing:
* deb: libssl-dev (Debian, Ubuntu, etc)
* rpm: openssl-devel (Fedora, CentOS, RHEL)
* csw: libssl_dev (Solaris)
* brew: openssl@1.1 (Mac OSX)
If openssl is already installed, check that ‘pkg-config’ is in your
PATH and PKG_CONFIG_PATH contains a openssl.pc file. If pkg-config
is unavailable you can set INCLUDE_DIR and LIB_DIR manually via:R CMD INSTALL –configure-vars=‘INCLUDE_DIR=… LIB_DIR=…’
解決方式：依指示到terminal安裝libssl-dev
sudo apt-get update
sudo apt-get install libssl-dev
錯誤訊息3
————————- ANTICONF ERROR —————————
Configuration failed because libxml-2.0 was not found. Try installing:
* deb: libxml2-dev (Debian, Ubuntu, etc)
* rpm: libxml2-devel (Fedora, CentOS, RHEL)
* csw: libxml2_dev (Solaris)
If libxml-2.0 is already installed, check that ‘pkg-config’ is in your
PATH and PKG_CONFIG_PATH contains a libxml-2.0.pc file. If pkg-config
is unavailable you can set INCLUDE_DIR and LIB_DIR manually via:R CMD INSTALL –configure-vars=‘INCLUDE_DIR=… LIB_DIR=…’
解決方式：依指示到terminal安裝libxml2-dev
sudo apt-get update
sudo apt-get install libxml2-dev
重新安裝
最後再回到R的環境下重新安裝rvest
install.packages("rvest")
安裝完成後，輸入以下指令確認是否有安裝成功。
library(rvest)