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CEXP(3) BSD Library Functions Manual CEXP(3) NAME cexp, cexpf -- complex exponential functions LIBRARY Math Library (libm, -lm) SYNOPSIS #include <complex.h> double complex cexp(double complex z); float complex cexpf(float complex z); DESCRIPTION The cexp() and cexpf() functions compute the complex exponential of z, also known as cis(z). RETURN VALUES For real numbers x and y, cexp() behaves according to Euler's formula: cexp(x + I*y) = (e**x * cos(y)) + (I * e**x * sin(y)) Generally speaking, infinities, zeroes and NaNs are handled as would be expected from this identity given the usual rules of floating-point arithmetic. However, care is taken to avoid generating NaNs when they are not deserved. For example, mathematically we expect that cimag(cexp(x + I*0)) = 0 regardless of the value of x, and cexp() pre- serves this identity even if x is infinity or NaN. Likewise, cexp(-infinity + I*y) = 0 and creal(cexp(infinity + I*y)) = infinity for any y (even though the latter property is only mathematically true for representable y.) If y is not finite, the sign of the result is indeter- minate. SEE ALSO complex(3), exp(3), math(3) STANDARDS The cexp() and cexpf() functions conform to ISO/IEC 9899:1999 ("ISO C99"). BSD March 6, 2011 BSD
NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | SEE ALSO | STANDARDS
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