Function pi() returns the value of PI.
pi()
Arguments：
Returns：
Example: Return the value of PI
UQLreturn pi()
return pi()
Result3.14159265358979
3.14159265358979
Example: Convert 123° to radian value
UQLreturn 123 * pi() / 180
return 123 * pi() / 180
Result2.14675497995303
2.14675497995303
