operatorslist

Documentation

Overview

Package operatorslist implements postfix calculator in two loops by editing the string containing the calculation.

Index

• func RPNOperatorsList(RPNInput string) float64

Examples

• RPNOperatorsList
• RPNOperatorsList (Exp)

Functions

func RPNOperatorsList

func RPNOperatorsList(RPNInput string) float64

RPNOperatorsList returns the result of a string in reverse polish notation (postfix) by exploding the string to a slice and editing the slice. Each iteration replaces an operation by its result until only a number is left.

If the expression is invalid, it fails failing if the expression is invalid. An invalid sign is interpreted as a value and the next operation panics.

A list of authorized operators is kept to find the fist one in the list. The expression is kept in a string.

Multiple conversions to test the validity of the expression is lowering efficiency. Removing subroutines has no visible impact here.

Example

if fmt.Print has an output (debug mode)

fmt.Printf("%f", RPNOperatorsList(values.RPNInput))

Output:
30.000000

Example (Exp)

fmt.Printf("%.13f", RPNOperatorsList(values.Input))

Output:
3.0001220703125