ndaumath

README

ndaumath

Definitive math libraries for calculations related to ndau

Purpose

This is intended to be the canonical location for all of the mathematical calculations for ndau.

The reason for this is that we are not just adding and subtracting -- we have EAI and SIB calculations that involve fractions, and we have to be very careful about things like overflow and precision.

We also use this library to define a robust test suite that is intended to be independent of implementation language. Thus, the same test suite can be used to prove that the math is correct no matter how it is implemented.

Finally, this repository should contain the ultimate reference documentation for ndau's mathematics.

Packages

The packages in this library contain the low-level math functions used by ndau.

Address

Addresses in ndau are similar but not identical to bitcoin addresses. In general, we were trying to create an address that was reasonably short (typeable by a human), identifiable as an ndau address (and not confused with addresses from other kinds of cryptocurrencies), had a built-in checksum capability, was case-insensitive, and allowed for a family of related address types. Its implementation details are hidden from normal uses.

B32

B32 is an implementation of a base32 encoding; this is preferable to base64 in that it is case-insensitive and avoids 1, 0, i, and l as problematic characters in many typefaces. Addresses use this library, as do keys.

BIP32

Functions to support Bitcoin BIP32, which is related to HD wallets.

Bitset256

Bitset256 is an implementation of a 256-bit bitset, indexed by a single byte. It's intended to be quite fast (certainly faster than a variable-width implementation).

Constants

A collection of the key constants in the ndau universe.

EAI

A careful implementation of the math behind EAI. EAI is complex and additionally is dependent on non-integral values. This library implements EAI using ratios of 64-bit numbers, using 128-bit math for some intermediate calculations to avoid overflow errors.

Key

Support for HD key derivation and manipulation derived from source code for a bitcoin-specific implementation.

KeyAddr

An implementation of a client-side Key generation and manipulation library in Go, that uses gomobile to generate Java and Objective-C code for use by Android and IoS applications.

ndauErr

Defines a couple of error types used by ndaumath libraries.

pricecurve

Functions that calculate prices on the ndau price curve (see details in ndau documentation)

Signature

Implementation of a generic concept of signatures so that ndau can someday have new signature types added if and when the existing signature types become obsolete.

Signed

An implementation of 64-bit signed math with overflows, errors, and a couple of special operations not usually found in such a library: MulDiv (with 128-bit intermediate operations), DivMod, and Exp that calculates e to a ratio rather than a floating point value.

The point of this library is to define calculations in a way that is guaranteed to be reproduceable and exact, in other languages and on other hardware.

Types

Defines some basic types for ndau -- the quanity of ndau, the way timestamps are represented, etc.

Unsigned

The equivalent of the Signed library, only Unsigned.

Words

An implementation of the BIP-0039 words-to-bits technique, using the same wordlist. It supports multiple languages in the API but so far only English is supported.