genedan / TmVal

Time Value of Money - a Python package for mathematical interest theory, annuity, and bond calculations.
https://genedan.com/tmval/docs
GNU General Public License v3.0
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enable pv and sv annuity methods to handle general accumulation functions #39

Open genedan opened 4 years ago

genedan commented 4 years ago

Right now the Annuity class isn't well-equipped to handle general accumulation functions. See Vaaler & Daniel textbook example 3.3.12 where the interest rate changes from .06 to .05. The shortcut formulas are only valid when the compound interest rate does not change.

genedan commented 4 years ago

There's a section further in the textbook that mentions general accumulation function, so we can wait until we reach that point.