[LSST|dm-users 584] Re: pipe_tasks 10.0+1 build error

[Robert Lupton the Good]

Is there some other problem with this test, giving different results under different circumstances (https://jira.lsstcorp.org/browse/DM-1984).  Or did we demonstrate that those circumstances were numpy version?

Anyway, I don't think that we should be using numpy.mean() on large arrays.  It's not guaranteed to be smart, and switching to 64-bit floats rather than fixing the algorithm is among the refuges of the scoundrel.

In this case you should either:
	subtract of the approximate mean and iterate, using np.mean()
or
	use afwMath.makeStatistics(im,  afwMath.MEAN).getValue() that /is/ guaranteed to be smart, and if it isn't we can fix it.
I appreciate the mean

						R

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