更新R版本到4.xxx

conda create -n r4-base
conda activate r4-base
conda config --add channels conda-forge
conda install -c conda-forge r-base #或者 conda install -c conda-forge r-base=4.1.3

安装后进入R环境

R

结果仍然是3.xxx版本

(r4-base) /mnt/workspace/wzf> R

R version 3.6.3 (2020-02-29) -- "Holding the Windsock"
Copyright (C) 2020 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

  Natural language support but running in an English locale

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

?怀疑是新安装的R没有添加到路径中

查看R环境：

(r4-base) /mnt/workspace/wzf> whereis R
R: /usr/bin/R /usr/lib/R /etc/R /usr/local/lib/R /usr/share/R /home/pai/envs/r4-base/bin/R

查看路径：

echo $PATH

?果然不在路径中，将/home/pai/envs/r4-base/bin/R添加到路径

r4-base) /mnt/workspace/wzf> export PATH="/home/pai/envs/r4-base/bin:$PATH"

重新进入R环境，成功变成4.xxx版本?