Pat Ferrel (JIRA)
2017-10-03 01:26:00 UTC
Pat Ferrel created MAHOUT-2019:
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Summary: SparseRowMatrix assign ops user for loops instead of iterateNonZero and so can be optimized
Key: MAHOUT-2019
URL: https://issues.apache.org/jira/browse/MAHOUT-2019
Project: Mahout
Issue Type: Bug
Components: Math
Affects Versions: 0.13.0
Reporter: Pat Ferrel
Assignee: Pat Ferrel
Fix For: 0.13.1
DRMs get blockified into SparseRowMatrix instances if the density is low. But SRM inherits the implementation of method like "assign" from AbstractMatrix, which uses nest for loops to traverse rows. For multiplying 2 matrices that are extremely sparse, the kind if data you see in collaborative filtering, this is extremely wasteful of execution time. Better to use a sparse vector's iterateNonZero Iterator for some function types.
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Summary: SparseRowMatrix assign ops user for loops instead of iterateNonZero and so can be optimized
Key: MAHOUT-2019
URL: https://issues.apache.org/jira/browse/MAHOUT-2019
Project: Mahout
Issue Type: Bug
Components: Math
Affects Versions: 0.13.0
Reporter: Pat Ferrel
Assignee: Pat Ferrel
Fix For: 0.13.1
DRMs get blockified into SparseRowMatrix instances if the density is low. But SRM inherits the implementation of method like "assign" from AbstractMatrix, which uses nest for loops to traverse rows. For multiplying 2 matrices that are extremely sparse, the kind if data you see in collaborative filtering, this is extremely wasteful of execution time. Better to use a sparse vector's iterateNonZero Iterator for some function types.
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This message was sent by Atlassian JIRA
(v6.4.14#64029)