Merge pull request #139 from ESMValGroup/remove_julia_instructions

Remove julia instructions

Author: SarahAlidoost

_episodes/02-installation.md

@@ -19,10 +19,8 @@ In this tutorial we will be using the
 install the ESMValTool. Other installation methods are also available, they can
 be found in the
 [documentation](https://docs.esmvaltool.org/en/latest/quickstart/installation.html).
-ESMValTool also contains diagnostics written in [Julia](https://julialang.org/).
-Because Julia cannot be installed by Conda, we will install Julia separately. We
-will first learn how to install Conda, Julia, and finally the ESMValTool. We end
-this chapter by testing that the installation was successful.
+We will first install Conda, and then ESMValTool. We end this chapter by testing
+that the installation was successful.
 
 ## Install Conda
 
@@ -124,90 +122,103 @@ instructions.
 
 ## Install Julia
 
+Some ESMValTool diagnostics are written in the Julia programming language.
+If you want a full installation of ESMValTool including Julia diagnostics, you need
+to make sure Julia is installed before installing ESMValTool.
+
+In this tutorial, we will not use Julia, but for reference, we have listed the steps
+to install Julia below.
 Complete instructions for installing Julia can be found on the [Julia
 installation page](https://julialang.org/downloads/platform/#linux_and_freebsd).
-In this tutorial, we will use the following steps. First, open a bash terminal
-and create a directory to install Julia in and cd into it
-
-```bash
-mkdir ~/julia
-cd ~/julia
-```
-
-Next, to download and extract the file `julia-1.0.5-linux-x86_64.tar.gz`, you can use the following commands::
-
-```bash
-wget https://julialang-s3.julialang.org/bin/linux/x64/1.0/julia-1.0.5-linux-x86_64.tar.gz
-tar -xvzf julia-1.0.5-linux-x86\_64.tar.gz
-```
-
-This will extract the files to a directory named `~/julia/julia-1.0.5`. To run
-Julia, you need to add the full path of Julia's `bin` folder to PATH environment
-variable. To do this, you can edit the `~/.bashrc` (or `~/.bash_profile`) file.
-Open the file in a text editor called ``nano``:
-
-```bash
-nano ~/.bashrc
-```
-
-and add a new line as follows at the
-bottom of the file:
-
-```bash
-export PATH="$PATH:$HOME/julia/julia-1.0.5/bin"
-```
-
-Finally, for the settings to take effect, either reload your bash profile
-
-```bash
-source ~/.bashrc
-```
-
-(or `source ~/.bash_profile`), or close the bash terminal window and open a new
-one.
-
-To check that the Julia executable can be found, run
-
-```bash
-which julia
-```
-
-to display the path to the Julia executable, it should be
-
-```
-~/julia/julia-1.0.5/bin/julia
-```
-{: .output}
-
-To test that Julia is installed correctly, run
-
-```bash
-julia
-```
-
-to start the interactive Julia interpreter. Press `Ctrl+D` to exit.
 
-> ## Text editor side note
+> ## Julia installation instructions
 >
-> No matter what editor you use, you will need to know where it searches
-> for and saves files. If you start it from the shell, it will (probably)
-> use your current working directory as its default location. We use ``nano``
-> in examples here because it is one of the least complex text editors.
-> Press <kbd>ctrl</kbd> + <kbd>O</kbd> to save the file,
-> and then <kbd>ctrl</kbd> + <kbd>X</kbd> to exit ``nano``.
-{: .callout}
+> First, open a bash terminal and create a directory to install Julia in and cd
+> into it
+>
+> ```bash
+> mkdir ~/julia
+> cd ~/julia
+> ```
+>
+> Next, to download and extract the file `julia-1.0.5-linux-x86_64.tar.gz`, you can use the following commands::
+>
+> ```bash
+> wget https://julialang-s3.julialang.org/bin/linux/x64/1.0/julia-1.0.5-linux-x86_64.tar.gz
+> tar -xvzf julia-1.0.5-linux-x86\_64.tar.gz
+> ```
+>
+> This will extract the files to a directory named `~/julia/julia-1.0.5`. To run
+> Julia, you need to add the full path of Julia's `bin` folder to PATH environment
+> variable. To do this, you can edit the `~/.bashrc` (or `~/.bash_profile`) file.
+> Open the file in a text editor called ``nano``:
+>
+> ```bash
+> nano ~/.bashrc
+> ```
+>
+> and add a new line as follows at the
+> bottom of the file:
+>
+> ```bash
+> export PATH="$PATH:$HOME/julia/julia-1.0.5/bin"
+> ```
+>
+> Finally, for the settings to take effect, either reload your bash profile
+>
+> ```bash
+> source ~/.bashrc
+> ```
+>
+> (or `source ~/.bash_profile`), or close the bash terminal window and open a new
+> one.
+>
+> To check that the Julia executable can be found, run
+>
+> ```bash
+> which julia
+> ```
+>
+> to display the path to the Julia executable, it should be
+>
+> ```
+> ~/julia/julia-1.0.5/bin/julia
+> ```
+> {: .output}
+>
+> To test that Julia is installed correctly, run
+>
+> ```bash
+> julia
+> ```
+>
+> to start the interactive Julia interpreter. Press `Ctrl+D` to exit.
+{: .solution}
 
 ## Install the ESMValTool package
 
-To install the ESMValTool package, run
+The ESMValTool package contains diagnostics scripts in four languages: R,
+Python, Julia and NCL. This introduces a lot of dependencies, and therefore the
+installation can take quite long. It is, however, possible to install
+'subpackages' for each of the languages. The following (sub)packages are
+available:
+
+- `esmvaltool-python`
+- `esmvaltool-ncl`
+- `esmvaltool-r`
+- `esmvaltool-julia`
+- `esmvaltool` --> the complete package, i.e. the combination of the above.
+
+For the tutorial, we will use only Python diagnostics. Thus, to install the
+ESMValTool-python package, run
 
 ```bash
-conda create -n esmvaltool -c conda-forge -c esmvalgroup esmvaltool
+conda create -n esmvaltool -c conda-forge -c esmvalgroup esmvaltool-python
 ```
 
 This will create a new [Conda
 environment](https://docs.conda.io/projects/conda/en/latest/user-guide/tasks/manage-environments.html)
-called `esmvaltool`, with the ESMValTool package and all of its dependencies
+called `esmvaltool`, with the ESMValTool-Python package and all of its dependencies
 installed in it.
 
 > ## Conda common problems