2015-02-10 22:49:10 +01:00
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# decimal [![Build Status](https://travis-ci.org/jellolabs/decimal.png?branch=master)](https://travis-ci.org/jellolabs/decimal)
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2015-02-10 21:33:58 +01:00
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Arbitrary-precision fixed-point decimal numbers in go.
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NOTE: can "only" represent numbers with a maximum of 2^31 digits after the decmial point.
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2015-02-10 22:49:10 +01:00
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## Features
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* addition, subtraction, multiplication with no loss of precision
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* division with specified precision
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* database/sql serialization/deserialization
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* json and xml serialization/deserialization
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## Notable users
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This is currently being used in production by [Spring](https://shopspring.com/), and has been since August 14, 2014.
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2015-02-10 21:33:58 +01:00
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## Usage
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```go
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package main
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import (
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"fmt"
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"github.com/jellolabs/decimal"
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)
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func main() {
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price, err := decimal.NewFromString("136.02")
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if err != nil {
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panic(err)
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}
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quantity := decimal.NewFromFloat(3)
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fee, _ := decimal.NewFromString(".035")
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taxRate, _ := decimal.NewFromString(".08875")
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subtotal := price.Mul(quantity)
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preTax := subtotal.Mul(fee.Add(decimal.NewFromFloat(1)))
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total := preTax.Mul(taxRate.Add(decimal.NewFromFloat(1)))
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fmt.Println("Subtotal:", subtotal)
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fmt.Println("Pre-tax:", preTax)
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fmt.Println("Taxes:", total.Sub(preTax))
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fmt.Println("Total:", total)
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fmt.Println("Tax rate:", total.Sub(preTax).Div(preTax))
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}
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```
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## Documentation
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http://godoc.org/github.com/jellolabs/decimal
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## License
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The MIT License (MIT)
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