The current package version available on this website is "GPT_1.0.zip", you can install the package by using "install.packages()" function or R program menu according to your operation system. Please download the package here. For now the latest beta version is available, with much faster calculation speed.
Linux/Unix/MacOS
R entironment: install.packages("GPT_1.0", dependencies = TRUE);
Shell: R CMD INSTALL package-GPT_1.0.tar.gz, please make sure the package you download is under the same directory.
Windows
Strat R program, and you can install packages from the menu: Packages --> Install package(s) form local zip file. And then, select the this package in the local path.
Video Tutorial
Installing R packages
Please note that you are running R program as administrator of the computer, otherwise you may not have permission to install the program or the packages. Also, If you are using Windows Vista, some permission limitation may occur if R program is installed on C:\ .