1EXP(3)                     Linux Programmer's Manual                    EXP(3)
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NAME

6       exp, expf, expl - base-e exponential function
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SYNOPSIS

9       #include <math.h>
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11       double exp(double x);
12       float expf(float x);
13       long double expl(long double x);
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15       Link with -lm.
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17   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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19       expf(), expl():
20           _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 ||
21           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
22           or cc -std=c99
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DESCRIPTION

25       The exp() function returns the value of e (the base  of  natural  loga‐
26       rithms) raised to the power of x.
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RETURN VALUE

29       On success, these functions return the exponential value of x.
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31       If x is a NaN, a NaN is returned.
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33       If x is positive infinity, positive infinity is returned.
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35       If x is negative infinity, +0 is returned.
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37       If the result underflows, a range error occurs, and zero is returned.
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39       If the result overflows, a range error occurs, and the functions return
40       +HUGE_VAL, +HUGE_VALF, or +HUGE_VALL, respectively.
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ERRORS

43       See math_error(7) for information on how to determine whether an  error
44       has occurred when calling these functions.
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46       The following errors can occur:
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48       Range error, overflow
49              errno  is  set  to ERANGE.  An overflow floating-point exception
50              (FE_OVERFLOW) is raised.
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52       Range error, underflow
53              errno is set to ERANGE.  An underflow  floating-point  exception
54              (FE_UNDERFLOW) is raised.
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CONFORMING TO

57       C99, POSIX.1-2001.  The variant returning double also conforms to SVr4,
58       4.3BSD, C89.
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SEE ALSO

61       cbrt(3), cexp(3), exp10(3), exp2(3), sqrt(3)
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COLOPHON

64       This page is part of release 3.53 of the Linux  man-pages  project.   A
65       description  of  the project, and information about reporting bugs, can
66       be found at http://www.kernel.org/doc/man-pages/.
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70                                  2010-09-20                            EXP(3)
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