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       ev - evaluate expressions




       Ev  evaluates  expressions  given  on  the  command line, and sends the
       results to the standard output, one per line.  An  expression  contains
       real numbers, function calls, and the following operators:

            +  -  *  /  ^

       Operators  are  evaluated  left  to  right,  except ’^’, which is right
       associative.  Powers have the highest  precedence;  multiplication  and
       division  are  evaluated  before addition and subtraction.  Expressions
       can be grouped with parentheses.  All values are double precision real.

       The following library of functions is available:

       if(cond, then, else)
                 if  cond  is  greater than zero, then is evaluated, otherwise
                 else is evaluated.

       select(N, a1, a2, ..)
                 return aN (N is rounded to the nearest  integer).   If  N  is
                 zero, the number of available arguments is returned.

       rand(x)   compute a random number between 0 and 1 based on x.

       floor(x)  return largest integer not greater than x.

       ceil(x)   return smallest integer not less than x.

       sqrt(x)   return square root of x.

       exp(x)    compute e to the power of x (e approx = 2.718281828).

       log(x)    compute the logarithm of x to the base e.

       log10(x)  compute the logarithm of x to the base 10.

       sin(x), cos(x), tan(x)
                 trigonometric functions.

       asin(x), acos(x), atan(x)
                 inverse trigonometric functions.

       atan2(y, x)
                 inverse tangent of y/x (range -pi to pi).


       To pass the square root of two and the sine of .5 to a program:

         program ‘ev ’sqrt(2)’ ’sin(.5)’‘


       Greg Ward


       icalc(1), rcalc(1)