Many of Guile's numeric procedures which accept any kind of numbers as arguments, including complex numbers, are implemented as Scheme procedures that use the following real numberbased primitives. These primitives signal an error if they are called with complex arguments.
Return x raised to the power of y. This procedure does not accept complex arguments.
Return the arc tangent of the two arguments x and y. This is similar to calculating the arc tangent of x / y, except that the signs of both arguments are used to determine the quadrant of the result. This procedure does not accept complex arguments.
Return e to the power of x, where e is the base of natural logarithms (2.71828...).
C functions for the above are provided by the standard mathematics
library. Naturally these expect and return double
arguments
(see Mathematics).
Scheme Procedure  C Function
 
$abs  fabs
 
$sqrt  sqrt
 
$sin  sin
 
$cos  cos
 
$tan  tan
 
$asin  asin
 
$acos  acos
 
$atan  atan
 
$atan2  atan2
 
$exp  exp
 
$expt  pow
 
$log  log
 
$sinh  sinh
 
$cosh  cosh
 
$tanh  tanh
 
$asinh  asinh
 
$acosh  acosh
 
$atanh  atanh

asinh
, acosh
and atanh
are C99 standard but might
not be available on older systems. Guile provides the following
equivalents (on all systems).