netPresentValue: netPresentValue
In AmateurECE/economics: Economic utilities

1	netPresentValue(cashFlows, interestRate)

`cashFlows`
`interestRate`

##---- Should be DIRECTLY executable !! ----
##-- ==>  Define data, use random,
##--	or do  help(data=index)  for the standard data sets.

## The function is currently defined as
function (cashFlows, interestRate) 
{
    exponent <- 0
    presentValue <- 0
    for (item in cashFlows) {
        presentValue <- presentValue + pv(item, interestRate, 
            exponent)
        exponent <- exponent + 1
    }
    presentValue
  }