h2o implementation in R

Question

I am learning h2o package now,

I installed h2o package from CRAN and couln't run this code

## To import small iris data file from H\ :sub:`2`\ O's package
irisPath = system.file("extdata", "iris.csv", package="h2o")
iris.hex = h2o.importFile(localH2O, path = irisPath, key = "iris.hex")

I am getting the below error,

Error in h2o.importFile(localH2O, path = irisPath, key = "iris.hex") : unused argument (key = "iris.hex")

My second question is, Do we have good resources to learn h2o in R apart from this:

http://h2o-release.s3.amazonaws.com/h2o/rel-lambert/5/docs-website/Ruser/rtutorial.html

My third question is I want to know how the h2o works in simple words.?

Please post one question at a time. What is the error message? — Roman Luštrik, Aug 22 '16 at 05:25
Thank you @Roman Lustrik, I donot know that, I will post only one question at a time from now. p — varun, Aug 22 '16 at 05:52
@Roman Lustrik, Thank you for your suggestion, I will do that from now. Please find the error i am getting which is edited — varun, Aug 22 '16 at 05:54

score 5 · Answer 1 · answered Aug 22 '16 at 18:02

The reason this code no longer works is that there was a breaking API change from H2O 2.0 to H2O 3.0 back in 2015. The docs you have discovered (probably via a Google search) are for a very old version of H2O 2.0. The up-to-date docs can always be found at http://docs.h2o.ai/h2o/latest-stable/h2o-docs/index.html

score 3 · Answer 2 · answered Aug 22 '16 at 07:40

Answering your error question:

H2O changed a bit from this documentation. Reading the iris file works as follows:

iris.hex = h2o.importFile(path = irisPath, destination_frame = "iris.hex")

Your second (and third question) is against SO rules. But below you will find a short list of resources:

H2O training materials (go to the h2o.ai website) and go to general documentation. You can find all the material there presented on h2o world 2015. There is also a link to h2o university.
Check their blog. There are some gold nuggets in there.
Read the booklets they have available on GBM, GLM, Deep Learning. They contain examples in R and Python.
Kaggle. Search the scripts / kernels for h2o.

As for your third question, read their "Why H2O pages".

score 1 · Answer 3 · answered Aug 23 '16 at 00:41

To answer your question about how H2O works it is little hard to put together here. however in nutshell, H2O is an open source enterprise ready machine intelligence engine with accessibility from popular machine learning languages i.e. R, Python as well as programming languages Java and Scala. Enterprise ready means users can distribute execution to multiple machines depending on extremely large size of data. The Java based core engine has builtin multiple algorithms implementation and any language interface goes through interpreter to H2O core engine which could be a distributed cluster to build models and score results. There is a lot in between so I would suggest visiting link below to learn more about H2O architecture and execution from various supported language:

http://docs.h2o.ai/h2o/latest-stable/h2o-docs/architecture.html

Thank you @Avkash Chauhan, I vl go through this link – varun Aug 23 '16 at 11:50 — varun, Aug 23 '16 at 11:50

score 0 · Answer 4 · answered Jan 03 '17 at 08:57

You can dig out more on H2O implementation in R starting from installation to implementation of h2o machine learning library in R. Go through this link. This also helps you in order to implement h2o machine learning on top of SparkR framework.

If you want to get an idea of h2o working prototype from very basic than follow this link. It provides the basic flavor of working prototype with code walk-through (quick learning tutorial).

Apart from above points, it also covers the following key points:

How to convert H2O data frame to R and Spark data frame and vice-versa
What are the pros and cons between SparkMLlib and H2O machine library
What are the strengths of h2o compare to other ML library
How to apply ML algorithm to R and Spark data frame etc.

h2o implementation in R

4 Answers4