Come together with the global Drupal community in Rotterdam, 28 Sept – 1 Oct 2026. Sessions, contribution, connection, and Early Bird savings until 8 June.In SQL, select 1/0 will result in NULL, not an error. If stddev is 0, then perhaps it will generates unexpected results.
If filtering it out using "where", it might cause problem with GROUP BY.
Work on simpletest, and then fix the problem.
Comments
Comment #1
danithaca commentedThis will not be fixed in the database implementation #481940: remove database implementation of the classical correlation-based algorithm. Still needs to be fixed for the memory implementation.
Comment #2
danithaca commentedfixed as of #483102: Internalize NAN support to the Vector/Matrix class
if stddev==0, then the correlation would be unset.