Tom Lane e1bd684a34 Add trigonometric functions that work in degrees.
The implementations go to some lengths to deliver exact results for values
where an exact result can be expected, such as sind(30) = 0.5 exactly.

Dean Rasheed, reviewed by Michael Paquier
2016-01-22 15:46:22 -05:00
..
2015-06-30 14:01:15 -04:00