install_tobac() installs the Python modules needed to run Tobac functions.
The packages are installed in a virtualenv, which by default is named
"harp-py". This virtual environment is the default virtual environment in
which all harp related Python modules are installed. If you already have the
"harp-py" virtualenv, you will be asked if you want to remove the virtualenv
prior to installation. Typically you would answer no to this.
install_tobac(envname = "harp-py", new_env = identical(envname, "harp-py"))The virtual environment into which to install the tobac Python modules. Default is "harp-py".
Whether to start from a new environment by removing the
envname if it already exists. The defulat is TRUE if envname already
exists, and you will be prompted if you want to remove the virtualenv
envname.