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Diffstat (limited to 'Eigen/src/SparseCore/SparseSparseProductWithPruning.h')
-rw-r--r--Eigen/src/SparseCore/SparseSparseProductWithPruning.h16
1 files changed, 8 insertions, 8 deletions
diff --git a/Eigen/src/SparseCore/SparseSparseProductWithPruning.h b/Eigen/src/SparseCore/SparseSparseProductWithPruning.h
index 3db01bf2d..48050077e 100644
--- a/Eigen/src/SparseCore/SparseSparseProductWithPruning.h
+++ b/Eigen/src/SparseCore/SparseSparseProductWithPruning.h
@@ -33,14 +33,6 @@ static void sparse_sparse_product_with_pruning_impl(const Lhs& lhs, const Rhs& r
// allocate a temporary buffer
AmbiVector<Scalar,StorageIndex> tempVector(rows);
- // estimate the number of non zero entries
- // given a rhs column containing Y non zeros, we assume that the respective Y columns
- // of the lhs differs in average of one non zeros, thus the number of non zeros for
- // the product of a rhs column with the lhs is X+Y where X is the average number of non zero
- // per column of the lhs.
- // Therefore, we have nnz(lhs*rhs) = nnz(lhs) + nnz(rhs)
- Index estimated_nnz_prod = lhs.nonZeros() + rhs.nonZeros();
-
// mimics a resizeByInnerOuter:
if(ResultType::IsRowMajor)
res.resize(cols, rows);
@@ -49,6 +41,14 @@ static void sparse_sparse_product_with_pruning_impl(const Lhs& lhs, const Rhs& r
typename evaluator<Lhs>::type lhsEval(lhs);
typename evaluator<Rhs>::type rhsEval(rhs);
+
+ // estimate the number of non zero entries
+ // given a rhs column containing Y non zeros, we assume that the respective Y columns
+ // of the lhs differs in average of one non zeros, thus the number of non zeros for
+ // the product of a rhs column with the lhs is X+Y where X is the average number of non zero
+ // per column of the lhs.
+ // Therefore, we have nnz(lhs*rhs) = nnz(lhs) + nnz(rhs)
+ Index estimated_nnz_prod = lhsEval.nonZerosEstimate() + rhsEval.nonZerosEstimate();
res.reserve(estimated_nnz_prod);
double ratioColRes = double(estimated_nnz_prod)/double(lhs.rows()*rhs.cols());