Blocked revisions 71837-71838 via svnmerge

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  r71837 | mark.dickinson | 2009-04-24 17:34:14 +0100 (Fri, 24 Apr 2009) | 4 lines

  Issue #5593: Use more robust test for double-rounding in test_fsum.
  While we're at it, use new unittest.skipUnless decorator to
  implement skipping for that test.
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  r71838 | mark.dickinson | 2009-04-24 17:37:22 +0100 (Fri, 24 Apr 2009) | 2 lines

  Remove unnecessary double negative
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