Accounting/math algorithms wanted

[M Nevar]

I am in the need of algorithms for two math/accounting calculations.

The first is for internal rate of return, and the second is for
least squares approximation.  

I have gotten books on least squares, but I can't decipher the
math notation enough to be sure about it.

If anyone has any ideas on these, I would really appreciate it.
-- 

                                Mark Nevar
                               	AT&T Technologies
                                Liberty Corner, NJ 
                                ...!ihnp4!bocar!man
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