+@deftypefn {C Function} SCM scm_c_make_rectangular (double re, double im)
+@deftypefnx {C Function} SCM scm_c_make_polar (double x, double y)
+Like @code{scm_make_rectangular} or @code{scm_make_polar},
+respectively, but these functions take @code{double}s as their
+arguments.
+@end deftypefn
+
+@deftypefn {C Function} double scm_c_real_part (z)
+@deftypefnx {C Function} double scm_c_imag_part (z)
+Returns the real or imaginary part of @var{z} as a @code{double}.
+@end deftypefn
+
+@deftypefn {C Function} double scm_c_magnitude (z)
+@deftypefnx {C Function} double scm_c_angle (z)
+Returns the magnitude or angle of @var{z} as a @code{double}.
+@end deftypefn
+