Downloading & Installing H2O
============================

This section describes how to download and install the latest stable version of H2O. These instructions are also available on the `H2O Download page <http://h2o-release.s3.amazonaws.com/h2o/latest_stable.html>`__. 

**Note**: To download the nightly bleeding edge release, go to `h2o-release.s3.amazonaws.com/h2o/master/latest.html <https://h2o-release.s3.amazonaws.com/h2o/master/latest.html>`__. Choose the type of installation you want to perform (for example, "Install in Python") by clicking on the tab. 

Download and Run
----------------

1. Click the ``Download H2O`` button on the `http://h2o-release.s3.amazonaws.com/h2o/latest_stable.html <http://h2o-release.s3.amazonaws.com/h2o/latest_stable.html>`__ page. This downloads a zip file that contains everything you need to get started.

2. From your terminal, run:

  ::

	cd ~/Downloads
	unzip h2o-3.20.0.1.zip
	cd h2o-3.20.0.1
	java -jar h2o.jar

3. Point your browser to http://localhost:54321.


Install in R
------------

Perform the following steps in R to install H2O. Copy and paste these commands one line at a time.

1. The following two commands remove any previously installed H2O packages for R.

 ::

	if ("package:h2o" %in% search()) { detach("package:h2o", unload=TRUE) }
	if ("h2o" %in% rownames(installed.packages())) { remove.packages("h2o") }

2. Next, download packages that H2O depends on.

 ::

    pkgs <- c("RCurl","jsonlite")
    for (pkg in pkgs) {
      if (! (pkg %in% rownames(installed.packages()))) { install.packages(pkg) }
    }

3. Download and install the H2O package for R.

 ::

	install.packages("h2o", type="source", repos=(c("http://h2o-release.s3.amazonaws.com/h2o/latest_stable_R")))

4. Optionally initialize H2O and run a demo to see H2O at work.

 ::

	library(h2o)
	localH2O = h2o.init() 
	demo(h2o.kmeans) 

Installing H2O's R Package from CRAN
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

You can alternatively install H2O’s R package from CRAN at `https://cran.r-project.org/web/packages/h2o/ <https://cran.r-project.org/web/packages/h2o/>`__.

Install in Python
-----------------

Run the following commands in a Terminal window to install H2O for Python. 

1. Install dependencies (prepending with `sudo` if needed):

 ::

	pip install requests
	pip install tabulate
	pip install scikit-learn
	pip install colorama
	pip install future

 **Note**: These are the dependencies required to run H2O. A complete list of dependencies is maintained in the following file: `https://github.com/h2oai/h2o-3/blob/master/h2o-py/conda/h2o/meta.yaml <https://github.com/h2oai/h2o-3/blob/master/h2o-py/conda/h2o/meta.yaml>`__

2. Run the following command to remove any existing H2O module for Python.

 ::

  pip uninstall h2o

3. Use ``pip`` to install this version of the H2O Python module.

 ::

	pip install -f http://h2o-release.s3.amazonaws.com/h2o/latest_stable_Py.html h2o

 **Note**: When installing H2O from ``pip`` in OS X El Capitan, users must include the ``--user`` flag. For example:

 ::
	
   pip install -f http://h2o-release.s3.amazonaws.com/h2o/latest_stable_Py.html h2o --user

4. Optionally initialize H2O in Python and run a demo to see H2O at work.

  ::

    python
    import h2o
    h2o.init()
    h2o.demo("glm")

Install on Anaconda Cloud
~~~~~~~~~~~~~~~~~~~~~~~~~

This section describes how to set up and run H2O in an Anaconda Cloud environment. Conda 2.7, 3.5, and 3.6 repos are supported as are a number of H2O versions. Refer to `https://anaconda.org/h2oai/h2o/files <https://anaconda.org/h2oai/h2o/files>`__ to view a list of available H2O versions.

Open a terminal window and run the following command to install H2O on the Anaconda Cloud. The H2O version in this command should match the version that you want to download. If you leave the h2o version blank and specify just ``h2o``, then the latest version will be installed.
      
   ::

     user$ conda install -c h2oai h2o=3.20.0.1

**Note**: For Python 3.6 users, H2O has ``tabulate>=0.75`` as a dependency; however, there is no ``tabulate`` available in the default channels for Python 3.6. This is available in the conda-forge channel. As a result, Python 3.6 users must add the ``conda-forge`` channel in order to load the latest version of H2O. This can be done by performing the following steps:

 ::

   conda create -n py36 python=3.6 anaconda
   source activate py36
   conda config --append channels conda-forge
   conda install -c h2oai h2o 

After H2O is installed, refer to the `Starting H2O from Anaconda <starting-h2o.html#from-anaconda>`__ section for information on how to start H2O and to view a GBM example run in Jupyter Notebook. 

Install on Hadoop
-----------------

1. Go to `http://h2o-release.s3.amazonaws.com/h2o/latest_stable.html <http://h2o-release.s3.amazonaws.com/h2o/latest_stable.html>`__. Click on the **Install on Hadoop** tab, and download H2O for your version of Hadoop. This is a zip file that contains everything you need to get started.

2. Unpack the zip file and launch a 6g instance of H2O. The example below describes how to unpack version 3.20.0.1. Replace this version with the version that you downloaded.

 ::

	unzip h2o-3.20.0.1-*.zip
	cd h2o-3.20.0.1-*
	hadoop jar h2odriver.jar -nodes 1 -mapperXmx 6g -output hdfsOutputDirName

3. Point your browser to H2O. (See "Open H2O Flow in your web browser" in the output below.)

 ::

	Determining driver host interface for mapper->driver callback...
	[Possible callback IP address: 172.16.2.181]
	[Possible callback IP address: 127.0.0.1]
	...
	Waiting for H2O cluster to come up...
	H2O node 172.16.2.188:54321 requested flatfile
	Sending flatfiles to nodes...
	[Sending flatfile to node 172.16.2.188:54321]
	H2O node 172.16.2.188:54321 reports H2O cluster size 1
	H2O cluster (1 nodes) is up
	(Note: Use the -disown option to exit the driver after cluster formation)

	Open H2O Flow in your web browser: http://172.16.2.188:54321

	(Press Ctrl-C to kill the cluster)
	Blocking until the H2O cluster shuts down...