In the context of understanding the precision of numeric data in SAS, we discovered the CONSTANT function and its "MACEPS" argument. MACEPS returns the "machine precision constant"; the SAS 9.2 Language Reference: Dictionary tells us that the following other arguments are available:
- The natural base
- Euler constant
- Pi
- Exact integer
- The largest double-precision number
- The logarithm of BIG
- The square root of BIG
- The smallest double-precision number
- The logarithm of SMALL
- The square root of SMALL
- Machine precision
- The logarithm of MACEPS
- The square root of MACEPS
A bit of research shows it has been available since at least V8, so my frustration of being unaware of it is compounded!