EV(1)							      General Commands Manual							     EV(1)

NAME

       ev - evaluate expressions

SYNOPSIS

       ev 'expr' ..

DESCRIPTION

       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).

EXAMPLE

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

	 program `ev 'sqrt(2)' 'sin(.5)'`

AUTHOR

       Greg Ward

SEE ALSO

       icalc(1), rcalc(1)

RADIANCE
							     10/28/96								     EV(1)