Add reciprocal and SinCos methods to IFloatingPoint

[lilinus]

Background and Motivation

Suggestion for the generic math. The mentioned methods are available in Math and MathF classes. I think it would be nice to add these to the IFloatingPoint interface.

Proposed API

namespace System
{
    public interface IFloatingPoint<TSelf>
    {
...
+        (TSelf, TSelf) SinCos(TSelf x);
+        TSelf ReciprocalEstimate(TSelf x);
+        TSelf ReciprocalSqrtEstimate(TSelf x);
...
    }
}

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Issue Details

---

Background and Motivation

Suggestion for the generic math. The mentioned methods are available in Math and MathF classes. I think it would be nice to add these to the IFloatingPoint interface.

Proposed API

namespace System
{
    public interface IFloatingPoint<TSelf>
    {
...
+        (TSelf, TSelf) SinCos(TSelf x);
+        TSelf ReciprocalEstimate(TSelf x);
+        TSelf ReciprocalSqrtEstimate(TSelf x);
...
    }
}

Author:	lilinus
Assignees:	-
Labels:	area-System.Numerics, untriaged
Milestone:	-

[huoyaoyuan]

They are more about low-level optimization, when you know the hardware support for some specific type, and looks unsuitable for generic. The interface should contain primitive methods only.

[tannergooding]

They are more about low-level optimization, when you know the hardware support for some specific type, and looks unsuitable for generic. The interface should contain primitive methods only.

The functions exist as more than just hardware optimizations and they are fully suitable for use in general algorithms, hence why they are on Math/MathF and not some other type.

These were simply missed from the initial preview due to the functions being new in .NET 6.

[bartonjs]

Video

Looks good as proposed.

namespace System
{
    public interface IFloatingPoint<TSelf>
    {
+        (TSelf Sin, TSelf Cos) SinCos(TSelf x);
+        TSelf ReciprocalEstimate(TSelf x);
+        TSelf ReciprocalSqrtEstimate(TSelf x);
    }
}