Documentation

[David Kincaid <ki...@gmail.com>]

I'm very new to Mahout and trying to learn starting with the classification
algorithms since I have an application for it. I've got the book "Mahout in
Action" and am working through chapter 14. This book is excellent, but I
have to say the Mahout documentation has some real shortcomings. Especially
for developers wanting to use Mahout from a Java program. Is there any
effort underway to improve this so that newbies like me would have an
easier time figuring out how to use what looks like a great library?

One specific example I am trying to find is where the class
org.apache.mahout.math.RandomAccessSparseVector is? It is used quite a bit
in this book, yet I can't seem to find the class anywhere. The javadocs for
0.6 don't show that class (or several others that are referenced in the
book). Can you help me understand where those classes are of if they have
been replaced with others already please point me at the replacements.

Thanks,

Dave

Re: Documentation

[Isabel Drost <is...@apache.org>]

On 16.11.2011 Ted Dunning wrote:
> One thing that you can do is to point out the problems and even suggest or
> provide some improvements.  Your eyes are still new and thus will see
> problems more clearly than ours.

One thing to note: Most of the Mahout documentation is online in our wiki - that 
wiki essentially is public, so if you do have some time left and spot an area 
that you think needs improvement, please do not hesitate to add information.

Also if you spot missing JavaDocs: Providing them is a very simple way to get 
your first patches in.


Isabel

Re: Documentation

[Ted Dunning <te...@gmail.com>]

David,

Thanks for showing up.  We can help much more here than on twitter.  A
shout out to Ellen for spotting you on twitter and sending you here.

On Tue, Nov 15, 2011 at 6:35 PM, David Kincaid <ki...@gmail.com>wrote:

> I'm very new to Mahout and trying to learn starting with the classification
> algorithms since I have an application for it. I've got the book "Mahout in
> Action" and am working through chapter 14. This book is excellent, but I
> have to say the Mahout documentation has some real shortcomings.


You are correct.  It does have some real shortcomings.


> Especially
> for developers wanting to use Mahout from a Java program.


Likewise.


> Is there any effort underway to improve this so that newbies like me would
> have an
> easier time figuring out how to use what looks like a great library?
>

Well, yes and no.  I try to make it cleaner where I can, but I have very
little time.  The recommendation stuff should have decent examples and
docs, but that isn't what you are after.

One thing that you can do is to point out the problems and even suggest or
provide some improvements.  Your eyes are still new and thus will see
problems more clearly than ours.


> One specific example I am trying to find is where the class
> org.apache.mahout.math.RandomAccessSparseVector is?


It is in the Mahout math package.  This is a separate package in order to
simplify using just that from other projects.

Use mvn install to get the mahout math package installed into your local
maven repository.  If you use IntelliJ, I recommend just giving it the top
level maven pom as the project file and it will find classes like this
across module boundaries very nicely.  There may be similar capabilities in
Eclipse as well.


> It is used quite a bit
> in this book, yet I can't seem to find the class anywhere. The javadocs for
> 0.6 don't show that class (or several others that are referenced in the
> book).


This is a bit unfortunate, but the math javadocs are separate:

http://search-lucene.com/jd/mahout/math/overview-tree.html

and

http://search-lucene.com/jd/mahout/math/org/apache/mahout/math/RandomAccessSparseVector.html

may help a bit.


> Can you help me understand where those classes are of if they have
> been replaced with others already please point me at the replacements.
>

Let us know if this helps or if there is more to say.