Troubleshooting - Aster Analytics

Teradata Aster Analytics Foundation User Guide

Product
Aster Analytics
Release Number
6.21
Published
November 2016
Language
English (United States)
Last Update
2018-04-14
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kiu1466024880662.ditamap
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dita:id
B700-1021
lifecycle
previous
Product Category
Software
  • Problem: The function runs slowly for large graphs or terminates unsuccessfully, displaying a failure message on the console.
  • Work Arounds:
    • Consult the logs for error message details and troubleshooting.
    • The logs can help determine the time taken for each iteration. If you know the number of iterations that the function takes (usually 25-50), you can estimate the total execution time.
    • All graph functions operate much faster on INTEGER and BIGINT single-column vertex ids. To generate an INTEGER vertex based graph, see Tips section above.
    • Compute the modularity in incremental steps by choosing a subset of nodes using the Sources argument.
    • If you already know some of the groupings in the graph, specify them with the CommunityAssociation argument.
    • If you specified the CommunityEdgeTable argument, the reason for the slow execution might be that the function is writing the community table to the database through JDBC. Run the function without the CommunityEdgeTable argument first, to obtain the modularity of the resultant graph.
  • Problem: The function terminates with errors on the vertices table or edges table.
  • Work Arounds:
    • Consult the logs for error message details and troubleshooting.
    • Ensure that all source and target vertices in the edges table are listed in the vertices table. Ensure that the columns representing source and target vertices are not NULL.
  • Problem: The function completes successfully; however, the results do not show a good modularity score or community detection.
  • Work Arounds:
    • Change the value of seed.
    • Multiply the edge weights by a constant.
    • Change the values in the Resolution argument.
    • If you already know some of the groupings in the graph, specify them with the CommunityAssociation argument.
  • Problem: The modularity score is poor.
  • Explanation: It may be that the graph has no inherent community structure.