kmath/docs/buffers.md

Buffers

Buffer is one of main building blocks of kmath. It is a basic interface allowing random-access read and write ( with MutableBuffer). There are different types of buffers:

• Primitive buffers wrapping like DoubleBuffer which are wrapping primitive arrays.
• Boxing ListBuffer wrapping a list
• Functionally defined VirtualBuffer which does not hold a state itself, but provides a function to calculate value
• MemoryBuffer allows direct allocation of objects in continuous memory block.

Some kmath features require a BufferFactory class to operate properly. A general convention is to use functions defined in Buffer and MutableBuffer companion classes. For example factory Buffer.Companion::auto in most cases creates the most suitable buffer for given reified type (for types with custom memory buffer it still better to use their own MemoryBuffer.create() factory).

Buffer performance

One should avoid using default boxing buffer wherever it is possible. Try to use primitive buffers or memory buffers instead.