# MacOS

Prerequisites for Arkouda can be installed using `Homebrew` or manually.

## Clone Arkouda Repository

Download, clone, or fork the [arkouda repo](https://github.com/Bears-R-Us/arkouda).

We encourage developers to fork the repo if they expect to make any changes to arkouda.
They can then clone their fork and add the Bears-R-Us repo as a remote:
```bash
git clone https://github.com/YOUR_FORK/arkouda.git
cd arkouda
git remote add upstream https://github.com/Bears-R-Us/arkouda.git
```

For users who aren't intending to make any changes, cloning the arkouda repo should be enough
```bash
git clone https://github.com/Bears-R-Us/arkouda.git
```

Further instructions assume that the current directory is the top-level directory of the arkouda repo.

## Python Environment - Anaconda

Arkouda provides 2 `.yml` files for configuration, one for users and one for developers.
The `.yml` files are configured with a default name for the environment, which is used in the example interactions with conda below. 
To provide a different name for the environment, use the `-n` or `--name` parameters when calling `conda env create`.

```bash
# We recommend running the full Anaconda 
brew install --cask anaconda

# Note - the exact path may vary based on the most current release of Anaconda and your mac's chipset
# Run the script to install Anaconda.
/opt/homebrew/Caskroom/anaconda/2022.10/Anaconda3-2022.10-MacOSX-arm64.sh

# initialize conda
conda init

# User conda env
conda env create -f arkouda-env.yml
conda activate arkouda

# Developer conda env
conda env create -f arkouda-env-dev.yml
conda activate arkouda-dev

# Install the Arkouda Client Package and add it to your PYTHONPATH.
# For this to work properly you need to change directories to where arkouda lives
pip install -e . --no-deps
export PYTHONPATH="${PYTHONPATH}:${PWD}"
```

## Updating Environment

As Arkouda progresses through its life-cycle, dependencies may change.
As a result, it is recommended that you keep your development environment in sync with the latest dependencies.
The instructions vary depending upon you preferred environment management tool.

### Anaconda

*If you provided a different name when creating the environment, replace `arkouda-dev` or `arkouda` with the name of your Conda environment.*

```bash
# developer environment update
conda env update -n arkouda-dev -f arkouda-env-dev.yml

# user environment update
conda env update -n arkouda -f arkouda-env.yml
```

## Install Chapel

It is recommended to compile Chapel from source. Alternatively, it can be installed via `Homebrew`.

### Build from Source (Recommended)

For convenience, the steps to install Chapel from source are detailed here.
If you need more information, please visit the [Chapel Quickstart Guide](https://chapel-lang.org/docs/usingchapel/QUICKSTART.html).

**Step 1** 
> Navigate to the directory where you want Chapel to be installed.
> You should not install Chapel in the arkouda directory

**Step 2**
> Download the current version of Chapel from [here](https://chapel-lang.org/download.html).

**Step 3**
> Unpack the release
> ```bash
> tar xzf chapel-2.1.0.tar.gz
> ```

**Step 4**
> Access the directory created when the release was unpacked
> ```bash
> cd chapel-2.1.0
> ```

**Step 5**
>Configure environment variables. *Please Note: This command assumes the use of `bash` or `zsh`. Please refer to the [Chapel Documentation](https://chapel-lang.org/docs/usingchapel/QUICKSTART.html#quickstart-with-other-shells) if you are using another shell.*
> ```bash
> source util/quickstart/setchplenv.bash
> ```

**Step 6**
> Update environment variables to the recommended settings. 
> ```bash
> brew install llvm
> export CHPL_LLVM=system
>
> brew install gmp
> export CHPL_GMP=system
> 
> export CHPL_RE2=bundled
>
> unset CHPL_DEVELOPER
> ```

> If you choose to use the packages bundled with Chapel, use the following settings.
> ```bash
> export CHPL_GMP=bundled
> export CHPL_LLVM=bundled
> export CHPL_RE2=bundled
> ```

**Step 7**
> Add the following to your `rc` file.
> ```bash
> # update paths to reflect where chapel and arkouda live on your machine
> export CHPL_HOME=/Users/USER/PATH_TO_CHPL/chapel-2.1.0
> # your binary might differ especially if you have a different chipset
> export PATH=$PATH:$CHPL_HOME/bin/darwin-arm64
> source ${CHPL_HOME}/util/setchplenv.bash
> export CHPL_LLVM=system # set to the same value as in the previous step
> export CHPL_GMP=system # set to the same value as in the previous step
> export CHPL_RE2=bundled
> export CHPL_COMM=none
> export CHPL_TARGET_CPU=native
> export ARKOUDA_QUICK_COMPILE=true
> export PYTHONPATH="${PYTHONPATH}:/Users/USER/PATH_TO_ARK/arkouda"
> ```

**Step 8**
> Source your `rc` file to set any environment variables, you might need to reactivate your conda environment
> ```bash
> source ~/.zshrc # or ~/.bashrc depending on your shell
> conda activate arkouda-dev # or the name of your conda environment
> ```

**Step 9**
> Use `make` to build Chapel
> ```bash
> make -j 8  # you can bump this up 16 if you have enough memory
> ```

**Step 10**
> Ensure that Chapel was built successfully
> ```bash
> chpl examples/hello3-datapar.chpl
> ./hello3-datapar
> ```

### Homebrew

Alternatively, you can use homebrew to install Chapel and all it's supporting dependencies.

```bash
brew install chapel
```

## Next Steps

We've installed Arkouda and its dependencies and built chapel with reasonable default environment variables.

Now you are ready to build the server! Follow the build instructions at [BUILD.md](BUILD.md).

We've set up chapel and arkouda to run locally with no communication! If you want to simulate running on a distributed machine follow
the instructions at [GASNet Development](https://bears-r-us.github.io/arkouda/developer/GASNET.html).