[kepler-dev] Token.toString method(s)

[Christopher Brooks]

I just checked in changes to DoubleMatrixToken and MatrixToken that
should do the trick.  I ended up using a Set, and I don't allocate it
unless there is a nil token.  We are definitely introducing overhead
in a few places, but I tried to be smart about it by only allocating
the set when we have a nil token.

We should probably review this code asap, perhaps Tuesday.
Maybe some of the Keplerites would like to call in? We would
review 1-2pm on Tuesday.  I'd probably review
Token, DoubleToken, ArrayToken, MatrixToken and DoubleMatrixToken
We'd review just the methods that involve nil.
If there is sufficient interest, I could set up a conference call.

_Christopher
--------

    At 01:07 AM 2/26/2006, Christopher Brooks wrote:
    >One issue here is that it would be nice if when we
    >have a DoubleMatrix that has a nil value, then if
    >we print it out and then read it back in with an
    >ExpressionReader, then we get the same matrix with
    >a nil value.  This points to printing nil as nil
    >not NaN.  So, we will need to keep a list of which
    >elements are nil. We probably want something fast,
    >like an ArrayList here, which as roughly O(n) time for
    >adds,  The ArrayList docs say:
    
    
    I hope this can be done in a way that doesn't
    introduce overhead when nil is not in use (the
    common case).  The intent of matrix tokens (vs.
    array tokens) is to maximize efficiency of numerical
    operations...
    
    Edward
    
    
    
    ------------
    Edward A. Lee
    Professor, Chair of the EE Division, Associate Chair of EECS
    231 Cory Hall, UC Berkeley, Berkeley, CA 94720
    phone: 510-642-0253 or 510-642-0455, fax: 510-642-2845
    eal at eecs.Berkeley.EDU, http://ptolemy.eecs.berkeley.edu/~eal  
--------