To: J3 J3/18-272 From: Lorri Menard Subject: Degree trigonometric functions Date: 2018-October-16 Reference: m215/18-139r1 I Introduction At m215 J3 agreed to consider adding degree-argument versions of some of the trigonometric intrinsic functions. Many, if not most, Fortran implementations support these degree-argument versions as extensions, and they are widely used. In the spirit of standardizing existing practice, we should add the following generic intrinsic functions to the standard: - ACOSD - ASIND - ATAN2D - ATAND - COSD - SIND - TAND All of these would be similar to their radian counterparts except that the argument(s) or return values would be in degrees. II Use cases This provides a portable mechanism for programs that have mathematical formulas that need the actual degrees, and don't want the overhead of converting to/from radians. III What I have in mind First, the prevailing principle is that only generic functions are to be added, even if some vendors (ahem) may have provided specific versions. Note that the hyperbolic functions (COSH, SINH, etc.) do not use radians and therefore need no degree equivalents. Finally, add the generic intrinsics listed above.