Ecosyste.ms: Packages

proxy.golang.org : github.com/govalues/money

Package money implements immutable amounts and exchange rates. Currency is represented as an integer index into an in-memory array that stores properties defined by ISO 4217: The currently supported currencies use scales of 0, 2, or 3: Amount is a struct with two fields: ExchangeRate is a struct with three fields: The range of an amount is determined by the scale of its currency. Similarly, the range of an exchange rate is determined by the scale of its quote currency. Here are the ranges for scales 0, 2, and 3: Subnoral numbers are not supported by the underlying decimal.Decimal type. Consequently, amounts and exchange rates between -0.00000000000000000005 and 0.00000000000000000005 inclusive are rounded to 0. The package provides methods for converting: See the documentation for each method for more details. Each arithmetic operation is carried out in two steps: The operation is initially performed using uint64 arithmetic. If no overflow occurs, the exact result is immediately returned. If an overflow does occur, the operation proceeds to step 2. The operation is repeated with increased precision using big.Int arithmetic. The result is then rounded to 19 digits. If no significant digits are lost during rounding, the inexact result is returned. If any significant digit is lost, an overflow error is returned. Step 1 was introduced to improve performance by avoiding heap allocation for big.Int and the complexities associated with big.Int arithmetic. It is expected that, in transactional financial systems, the majority of arithmetic operations will successfully compute an exact result during step 1. The following rules are used to determine the significance of digits during step 2: Amount.Add, Amount.Sub, Amount.SubAbs, Amount.Mul, Amount.FMA, Amount.Quo, Amount.QuoRem, ExchangeRate.Conv, ExchangeRate.Mul, ExchangeRate.Inv: All digits in the integer part are significant. In the fractional part, digits are significant up to the scale of the currency. Amount.Rat: All digits in the integer part are significant, while digits in the fractional part are considered insignificant. Implicit rounding is applied when a result exceeds 19 digits. In such cases, the result is rounded to 19 digits using half-to-even rounding. This method ensures that rounding errors are evenly distributed between rounding up and rounding down. For all arithmetic operations, the result is the one that would be obtained by computing the exact mathematical result with infinite precision and then rounding it to 19 digits. In addition to implicit rounding, the package provides several methods for explicit rounding: See the documentation for each method for more details. All methods are panic-free and pure. Errors are returned in the following cases: Currency Mismatch. All arithmetic operations, except for Amount.Rat, return an error if the operands are denominated in different currencies. Division by Zero. Unlike the standard library, Amount.Quo, Amount.QuoRem, Amount.Rat, and ExchangeRate.Inv do not panic when dividing by 0. Instead, they return an error. Overflow. Unlike standard integers, there is no "wrap around" for amounts at certain sizes. Arithmetic operations return an error for out-of-range values. Underflow. All arithmetic operations, except for ExchangeRate.Inv and ExchangeRate.Mul, do not return an error in case of underflow. If the result is an amount between -0.00000000000000000005 and 0.00000000000000000005 inclusive, it is rounded to 0. ExchangeRate.Inv and ExchangeRate.Mul return an error in cases of underflow, as the result of these operations is an exchange rate, and exchange rates cannot be 0. This example calculates the effective interest rate for a 10% nominal interest rate compounded monthly on a USD 10,000 balance. In this example, a loan amortization table is generated for a loan with an initial amount of USD 12,000, an annual interest rate of 10%, and a repayment period of 1 year. In this example, we parse the string "840D000000001234", which represents -12.34 USD, according to the specification for "DE54, Additional Amounts" in ISO 8583. This is an example of how to a parse a monetary amount formatted as money.proto. This is an example of how to a parse a monetary amount formatted according to Stripe API specification. In this example, the sales tax amount is calculated for a product with a given price after tax, using a specified tax rate.

Registry - Source - Documentation - JSON
purl: pkg:golang/github.com/govalues/money
Keywords: currencies, currencies-conversions, currency, decimal, exchange-rate, financial, floating-point, go, golang, iso-4217, money
License: MIT
Latest release: 5 months ago
First release: about 1 year ago
Namespace: github.com/govalues
Stars: 8 on GitHub
Forks: 1 on GitHub
See more repository details: repos.ecosyste.ms
Last synced: 12 days ago

• Readme
• Versions 10
• Dependent Packages 0
• Maintainers 0