       The  following  procedures  provide command interfaces to the expr math
       functions. They take the same arguments as the expr functions  and  may
       take expressions as arguments.

              abs         acos        asin       atan2
              atan        ceil        cos        cosh
              double      exp         floor      fmod
              hypot       int         log10      log
              pow         round       sin        sinh
              sqrt        tan         tanh
