updated docs

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extra : convert_revision : svn%3Afdd8eb12-d10e-0410-9acb-85c331704f74/trunk%403999

docs/docs/optimization.xml

@@ -370,7 +370,9 @@ subject to the following constraint:
       sum(alpha) == nu*y.size() 
       0 <= min(alpha) && max(alpha) <= 1 
       trans(y)*alpha == 0
-   Where f is convex.  This means that Q should be symmetric and positive-semidefinite.
+
+   Where all elements of y must be equal to +1 or -1 and f is convex.  
+   This means that Q should be symmetric and positive-semidefinite.
 </pre>
 <br/>
                 This object implements the strategy used by the LIBSVM tool.  The following papers