1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83
|
//------------------------------------------------------------------------------
// GrB_Semiring_new: create a new semiring
//------------------------------------------------------------------------------
// SuiteSparse:GraphBLAS, Timothy A. Davis, (c) 2017-2022, All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
//------------------------------------------------------------------------------
// A GraphBLAS Semiring consists of two components: "add" and "multiply".
// These components imply three domains: ztype, xtype, and ytype.
// The "add" is an associative and commutative monoid, which is a binary
// operator that works on a single type, ztype = add(ztype,ztype). The add
// monoid also includes an identity value, called "zero", so that
// add(x,zero)=add(zero,x)=x. For most algebras, this "zero" is a plain zero
// in the usual sense, but this is not the case for all algebras. For example,
// for the max-plus algebra, the "add" operator is the function max(a,b), and
// the "zero" for this operator is -infinity since max(a,-inf)=max(-inf,a)=a.
// The "multiply" is a binary operator z = multiply(x,y). It has no
// restrictions, except that the type of z must exactly match the ztype
// of the add monoid. That is, the types for the multiply operator are
// ztype = multiply (xtype, ytype). When the semiring is applied to two
// matrices A and B, where (A,B) appear in that order in the method, the
// multiply operator is always applied as z = multiply (A(i,j),B(i,j)). The
// two input operands always appear in that order. That is, the multiply
// operator is not assumed to be commutative.
#include "GB.h"
#include "GB_Semiring_new.h"
#define GB_FREE_ALL \
{ \
GB_FREE (semiring, header_size) ; \
}
GrB_Info GrB_Semiring_new // create a semiring
(
GrB_Semiring *semiring, // handle of semiring to create
GrB_Monoid add, // additive monoid of the semiring
GrB_BinaryOp multiply // multiply operator of the semiring
)
{
//--------------------------------------------------------------------------
// check inputs
//--------------------------------------------------------------------------
GrB_Info info ;
GB_WHERE1 ("GrB_Semiring_new (&semiring, add, multiply)") ;
GB_RETURN_IF_NULL (semiring) ;
(*semiring) = NULL ;
GB_RETURN_IF_NULL_OR_FAULTY (add) ;
GB_RETURN_IF_NULL_OR_FAULTY (multiply) ;
ASSERT_MONOID_OK (add, "semiring->add", GB0) ;
ASSERT_BINARYOP_OK (multiply, "semiring->multiply", GB0) ;
//--------------------------------------------------------------------------
// allocate the semiring
//--------------------------------------------------------------------------
size_t header_size ;
(*semiring) = GB_MALLOC (1, struct GB_Semiring_opaque, &header_size) ;
if (*semiring == NULL)
{
// out of memory
return (GrB_OUT_OF_MEMORY) ;
}
(*semiring)->header_size = header_size ;
//--------------------------------------------------------------------------
// create the semiring
//--------------------------------------------------------------------------
GB_OK (GB_Semiring_new (*semiring, add, multiply)) ;
return (GrB_SUCCESS) ;
}
|