Swift-Numerics

Introduction

Swift-numerics provides a set of modules that support numerical computing in Swift. These modules fall broadly in two categories:

• API that is too specialized to go into the standard library, but which is sufficiently general to be centralized in a single common package.
• API that is under active development toward possible future inclusion in the standard library.

There is some overlap between these two categories, and API that begins in the first category may migrate to the second as it matures and new uses are discovered.

Swift-numerics modules are fine-grained; if a user needs support for Complex numbers, they can import the Complex module without pulling in a module for linear algebra as well.

Swift-numerics modules have minimal dependencies on other projects. It assumes only the availability of the Swift and C standard libraries, and the runtime support provided by compiler-rt. Future expansion may assume the availability of other standard interfaces such as BLAS and LAPACK, but modules with more specialized dependencies probably belong in a separate package.

Process

Swift-numerics changes are not expected to go through swift-evolution. For some modules, swift-numerics may act as a staging area for the standard library, but in those cases, the expectation is that swift-evolution review will take place at the point that the module is proposed for inclusion. It's good to keep that process in mind, however, and document why you're making the decisions that you are, so that reviewers can refer to those rationales when a module comes up for swift-evolution.

Swift-numerics uses github issues to track bugs and features, and pull requests for development.

To propose a new module:

1. Raise an issue with the [new module] tag.
2. Raise a PR with an implementation sketch.
3. Once you have some consensus, ask an admin to create a feature branch against which PRs can be raised.
4. When the design has stabilized and is functional enough to be useful, raise a PR to merge the new module to master.

To propose a new feature for an existing module:

1. Raise an issue with the [enhancement] tag.
2. Raise a PR with an implementation, and discuss the implementation there.
3. Once there is consensus that the new feature is desirable and the design is suitable, it can be merged.

To fix a bug, or make smaller improvements:

1. Raise a PR with your change. Be sure to add test coverage for whatever changes you are making.

Modules

1. ElementaryFunctions
2. Complex

Future expansion

1. Approximate Equality
2. Large Fixed-Width Integers
3. Arbitrary-Precision Integers
4. Shaped Arrays
5. Decimal Floating-point
6. Float16