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33 .Nd complex exponential functions
39 .Fn cexp "double complex z"
41 .Fn cexpf "float complex z"
47 functions compute the complex exponential of
58 behaves according to Euler's formula:
59 .Bd -ragged -offset indent
65 .Fa y Ns Pc Pc + Po Ns
75 Generally speaking, infinities, zeroes and \*(Nas are handled as would
76 be expected from this identity given the usual rules of floating-point
78 However, care is taken to avoid generating \*(Nas when they are not deserved.
79 For example, mathematically we expect that
82 = 0 regardless of the value of
86 preserves this identity even if
90 .Fn cexp "-\*(If + I*y"
93 .Fn cexp "\*(If + I*y" Fc
97 (even though the latter property is only mathematically true for
102 is not finite, the sign of the result is indeterminate.