svn commit: r1619229 - /mahout/site/mahout_cms/trunk/content/users/sparkbindings/play-with-shell.mdtext

[dl...@apache.org]

Author: dlyubimov
Date: Wed Aug 20 20:57:21 2014
New Revision: 1619229

URL: http://svn.apache.org/r1619229
Log:
CMS commit to mahout by dlyubimov

Modified:
    mahout/site/mahout_cms/trunk/content/users/sparkbindings/play-with-shell.mdtext

Modified: mahout/site/mahout_cms/trunk/content/users/sparkbindings/play-with-shell.mdtext
URL: http://svn.apache.org/viewvc/mahout/site/mahout_cms/trunk/content/users/sparkbindings/play-with-shell.mdtext?rev=1619229&r1=1619228&r2=1619229&view=diff
==============================================================================
--- mahout/site/mahout_cms/trunk/content/users/sparkbindings/play-with-shell.mdtext (original)
+++ mahout/site/mahout_cms/trunk/content/users/sparkbindings/play-with-shell.mdtext Wed Aug 20 20:57:21 2014
@@ -137,16 +137,15 @@ We hope that we could show that Mahout's
 We put all the commands for ordinary least squares into a function ```ols```. 
 
 <div class="codehilite"><pre>
-def ols(drmX: DrmLike[Int], y: Vector) = {
+def ols(drmX: DrmLike[Int], y: Vector) = 
+  solve(drmX.t %*% drmX, drmX.t %*% y)(::,0)
 
-  val XtX = (drmX.t %*% drmX).collect
-  val Xty = (drmX.t %*% y).collect(::, 0)
-
-  solve(XtX, Xty)
-}
 </pre></div>
 
-And we define a function ```goodnessOfFit``` that tells how well a model fits the target variable:
+Note that DSL declares implicit `collect` if coersion rules require an in-core argument. Hence, we can simply
+skip explicit `collect`s. 
+
+Next, we define a function ```goodnessOfFit``` that tells how well a model fits the target variable:
 
 <div class="codehilite"><pre>
 def goodnessOfFit(drmX: DrmLike[Int], beta: Vector, y: Vector) = {