 # Php Programming Code Examples

## Php > Algorithms Code Examples

### A suite of financial management functions including present and future

A suite of financial management functions including present and future value of an annuity and a loan payment calculation function <?php /* VARIABLES: \$m = number of periods per year. For instance, if you are For instance, if you are making payments monthly then this number is 12. \$n = total number of periods. For instance, if you are compounding monthly for 5 years, this number would be 60 (12 months x 5 years). \$R = annual interest rate (represented as a decimal, 8% = .08) \$pmt = first or re-occuring payment or receipt (this number cannot vary for differing cash flows) \$principal = present value of an annuity, or current principal of a loan used in the PaymentCalc function */ // present value of an Annuity // uses include defining Remaining Principal of a loan/mortgage function PVannuity (\$m,\$n,\$R,\$pmt) { \$Z = 1 / (1 + (\$R/\$m)); return (\$pmt * \$Z * (1 - pow(\$Z,\$n)))/(1 - \$Z); } // Given the compounding, principal, interest rate, you can calculate the monthly payment function PaymentCalc (\$m,\$n,\$R,\$principal) { \$Z = 1 / (1 + (\$R/\$m)); return ((1 - \$Z) * \$principal) / (\$Z * (1 - pow(\$Z,\$n))); } // future value of an Annuity function FVannuity (\$m,\$n,\$R,\$pmt) { return \$pmt * ((pow((1 + \$R/\$n),\$m) - 1)/(\$R/\$n)); } // present value of a single payment function PVsingle (\$m,\$n,\$R,\$pmt) { return \$pmt * pow((1 + \$R/\$m),-\$n); } // future value of a single payment function FVsingle (\$m,\$n,\$R,\$pmt) { return \$pmt * pow((1 + \$R/\$m),\$n); } // future value of a single payment with continuous compounding function FVperp (\$m,\$n,\$R,\$pmt) { return \$pmt * exp(\$R * (\$n/\$m)); } ?>