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//------------------------------------------------------------------------------
// GB_convert_sparse_to_hyper_test: test for sparse to hypersparse conversion
//------------------------------------------------------------------------------
// SuiteSparse:GraphBLAS, Timothy A. Davis, (c) 2017-2022, All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
//------------------------------------------------------------------------------
// Returns true if a sparse matrix should be converted to hypersparse.
// Returns false if the matrix should stay sparse.
// A matrix with vdim <= 1 must always be sparse, not hypersparse;
// that is, a GrB_Vector is never hypersparse.
#include "GB.h"
bool GB_convert_sparse_to_hyper_test // test sparse to hypersparse conversion
(
float hyper_switch, // A->hyper_switch
int64_t k, // # of non-empty vectors of A (an estimate is OK)
int64_t vdim // A->vdim
)
{
// get the vector dimension of this matrix
float n = (float) vdim ;
// ensure k is in the range 0 to n, inclusive
k = GB_IMAX (k, 0) ;
k = GB_IMIN (k, n) ;
return (n > 1 && (((float) k) <= n * hyper_switch)) ;
}
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