matmul ( tensor1: tensor tensor2: tensor -- tensor3: tensor )
Tensors » Manipulating Tensors

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Vocabulary
tensors

Inputs

tensor1	a tensor
tensor2	a tensor

Outputs

tensor3

a tensor

Word description
Performs n-dimensional matrix multiplication on two tensors, where tensor1 has shape ...xmxn and tensor1 has shape ...xnxp.

Errors
Throws a shape-mismatch-error if the bottom two dimensions of the tensors passed do not take the form mxn and nxp and/or the top dimensions do not match.

Definition

USING: accessors combinators kernel math sequences
specialized-arrays.instances.alien.c-types.float tensors.private
typed ;

IN: tensors

TYPED:: matmul
    ( tensor1: tensor tensor2: tensor -- tensor3: tensor )
    tensor1 tensor2 check-matmul-shape
    tensor1 shape>> unclip-last-slice :> n unclip-last-slice
    :> m :> top-shape tensor2 shape>> last :> p top-shape
    product :> top-prod top-shape { m p } append
    dup product (float-array) :> vec3 top-prod [
        :> i tensor1 vec>> m n * i * m n * make-subseq
        tensor2 vec>> n p * i * n p * make-subseq vec3 m p * i *
        m p * make-subseq m n p {
            { [ n 4 mod 0 = ] [ 2d-matmul-simd ] }
            { [ n 4 < ] [ 2d-matmul ] }
            [ i 2d-matmul-mixed ]
        } cond
    ] each-integer vec3 <tensor> ;