Guile Reference Manual
21.2.11 Arithmetic Functions
 Scheme Procedure: + z1 ...
 Return the sum of all parameter values. Return 0 if called without any
parameters.
 Scheme Procedure:  z1 z2 ...
 If called with one argument z1, z1 is returned. Otherwise
the sum of all but the first argument are subtracted from the first
argument.
 Scheme Procedure: * z1 ...
 Return the product of all arguments. If called without arguments, 1 is
returned.
 Scheme Procedure: / z1 z2 ...
 Divide the first argument by the product of the remaining arguments. If
called with one argument z1, 1/z1 is returned.
 Scheme Procedure: abs x

 C Function: scm_abs (x)
 Return the absolute value of x.
x must be a number with zero imaginary part. To calculate the
magnitude of a complex number, use magnitude
instead.
 Scheme Procedure: max x1 x2 ...
 Return the maximum of all parameter values.
 Scheme Procedure: min x1 x2 ...
 Return the minimum of all parameter values.
 Scheme Procedure: truncate
 Round the inexact number x towards zero.
 Scheme Procedure: round x
 Round the inexact number x towards zero.
 Scheme Procedure: floor x
 Round the number x towards minus infinity.
 Scheme Procedure: ceiling x
 Round the number x towards infinity.
For the truncate
and round
procedures, the Guile library
exports equivalent C functions, but taking and returning arguments of
type double
rather than the usual SCM
.
 C Function: double scm_truncate (double x)

 C Function: double scm_round (double x)
For floor
and ceiling
, the equivalent C functions are
floor
and ceil
from the standard mathematics library
(which also take and return double
arguments).