Hi,
 I was wondering why Ruby Matrix class doesn't creates objects which are
editable? 

That is,
m = Matrix[[2,3,4]]
m[0,0]= 5
NoMethodError: undefined method `[]=' for Matrix[[2, 3, 4]]:Matrix
	from (irb):11
gives error,

as a workaround I have seen people/myself opened the matrix class and defined the
'[]=' method such that, '@rows' variable is edited.

    def []=(i,j,val)
      @rows[i][j] = val
    end

Is it safe to do this?
Ditto for the Vector class? why are objects of these classes not editable?

Second, if I want to change the class of an object? Is it possible to do so?
Say, I want an object of Matrix class to automatically changed to DMatrix,
which is a derived class, then how do I do so? 

Thanks for your help.

Regards,
-- 
Surendra Singhi
http://ssinghi.kreeti.com, http://www.kreeti.com
Read my blog at: http://cuttingtheredtape.blogspot.com/
,----
| Great wits are sure to madness near allied,
| And thin partitions do their bounds divide.
| 
|     (John Dryden, Absalom and Achitophel, 1681)
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