Function future_value_schedule 

pub fn future_value_schedule<T>(
    rates: &[f64],
    present_value: T,
) -> FinanceResult<f64>
where
    T: Into<f64> + Copy,

Calculates a future value based on rates that change for each period.

Related functions:

• To calculate the future value with varying rates and return a struct that can produce the period-by-period values use future_value_schedule_solution.
• If there is a single fixed rate use [future_value] or future_value_solution.

Arguments

• rates - A collection of rates, one for each period.
• present_value - The starting value of the investment.

Errors

The call returns FinanceError if any of the rates is less than -1.0 as this would mean the investment is losing more than its full value.

Examples

Calculate the value of an investment whose rates vary by year.

use finance_solution::*;
// The rates vary by year: 4% followed by -3.9%, 10.6%, and -5.7%.
let rates = [0.04, -0.039, 0.106, -0.057];

// The initial investment is $75,000.
let present_value = -75_000.00;

let future_value = future_value_schedule(&rates, present_value).unwrap();
dbg!(&future_value);
assert_rounded_4(78_178.0458, future_value);

Error case: One of the rates shows a drop of over 100%.

let rates = [0.116, -100.134, -0.09, 0.086];
let present_value = -4_000.00;
let err = future_value_schedule(&rates, present_value).unwrap_err();
assert!(matches!(err, FinanceError::InvalidRate { .. }));

Errors

Returns FinanceError::InvalidRate if any rate is out of domain, or FinanceError::NonFinite for non-finite inputs/results. An empty rates slice is valid and means zero periods (returns -present_value).