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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calculate delta_t for any function #23

Open genedan opened 4 years ago

genedan commented 4 years ago

so far I'm only able to calculate this for the very special cases of simple interest/discount, and compound rates

however, for more general cases, we'd need calculus since \delta_t = \frac{a`(t)}{a(t)}, which requires taking the derivative of of the accumulation function