If you look at the differing results carefully, there's this one:
*** 3249,3255 ****
! [(0,0),(3,0),(4,5),(1,6)] | (-5,-12) | [(0,-0),(-15,-36),(40,-73),(67,-42)]
--- 3249,3255 ----
! [(0,0),(3,0),(4,5),(1,6)] | (-5,-12) | [(0,0),(-15,-36),(40,-73),(67,-42)]
(Third column is first multiplied by second).
I wonder why the expected file has a -0 only in the second position and
not both first and second. These are both positive zeroes being
multiplied by a negative number. Why is 0 * -12 = -0 yet 0 * -5 = 0?
What is going on? Is the sign suppressed for negative zeros only in the
first coordinate? I suppose this is just a side effect of how
float8_mi, _pl, _mul work (in point_mul_point).
Anyway maybe your test case should use more of the float8 op
combinations in order to show the difference.
--
Álvaro Herrera https://www.2ndQuadrant.com/
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