Fcn.md

@@ -10,7 +10,11 @@ The module supports a number of different types of mathematical functions:
 - Square root ( `sqrt()` )
 - ***Single argument*** LIGO math functions defined in the `inlineMath_x86_asm.h` header
     - For the functions named above you must use the non-LIGO name, ex `sin()` instead of `lsin()` as the RCG does the conversion
-- Combinations of the above functions and constants
+- Combinations of the above functions.
+- Combinations with constants defined in 'inlineMath_x86_asm.h'
+    - `M_PI` -  3.14159265358979323846
+    - `M_TWO_PI` - 6.28318530717958647692
+    - `M_SQRT2` - 1.41421356237309504880
 
 ## Operation
 
@@ -22,7 +26,7 @@ Once the function has been defined, click on OK and the function will be incorpo
 - `sin(u[1])`
 - `sin(u[1]) + cos(u[2])+log10(u[3])*fabs(u[4])/sqrt(u[5])`
 - `lceil(u[1])`
-- `u[1] * (180 / M_PI)`
+- `u[1] * (180.0 / M_PI)`
 
 
 ## Examples