* lib/matrix: Add Matrix#round

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@32350 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,7 @@
+Fri Jul  1 15:10:22 2011  Marc-Andre Lafortune  <ruby-core@marc-andre.ca>
+
+	* lib/matrix: Add Matrix#round
+
 Fri Jul  1 11:41:12 2011  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* string.c (tr_trans): free heap ptr when the str is not embeded.

NEWS

@@ -164,6 +164,7 @@ with all sufficient information, see the ChangeLog file.
     * Matrix#normal?
     * Matrix#orthogonal?
     * Matrix#permutation?
+    * Matrix#round
     * Matrix#symmetric?
     * Matrix#unitary?
     * Matrix#upper_triangular?

lib/matrix.rb

@@ -89,6 +89,7 @@ end
 # * <tt> #determinant                   </tt>
 # * <tt> #det                           </tt>
 # * <tt> #rank                          </tt>
+# * <tt> #round                         </tt>
 # * <tt> #trace                         </tt>
 # * <tt> #tr                            </tt>
 # * <tt> #transpose                     </tt>
@@ -1125,6 +1126,12 @@ class Matrix
     rank
   end
 
+  # Returns a matrix with entries rounded to the given precision
+  # (see Float#round)
+  #
+  def round(ndigits=0)
+    map{|e| e.round(ndigits)}
+  end
 
   #
   # Returns the trace (sum of diagonal elements) of the matrix.