1EXP(3) Linux Programmer's Manual EXP(3)
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6 exp, expf, expl - base-e exponential function
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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(): _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 ||
20 _ISOC99_SOURCE; or cc -std=c99
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23 The exp() function returns the value of e (the base of natural loga‐
24 rithms) raised to the power of x.
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27 On success, these functions return the exponential value of x.
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29 If x is a NaN, a NaN is returned.
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31 If x is positive infinity, positive infinity is returned.
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33 If x is negative infinity, +0 is returned.
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35 If the result underflows, a range error occurs, and zero is returned.
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37 If the result overflows, a range error occurs, and the functions return
38 +HUGE_VAL, +HUGE_VALF, or +HUGE_VALL, respectively.
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41 See math_error(7) for information on how to determine whether an error
42 has occurred when calling these functions.
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44 The following errors can occur:
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46 Range error, overflow
47 errno is set to ERANGE. An overflow floating-point exception
48 (FE_OVERFLOW) is raised.
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50 Range error, underflow
51 errno is set to ERANGE. An underflow floating-point exception
52 (FE_UNDERFLOW) is raised.
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55 C99, POSIX.1-2001. The variant returning double also conforms to SVr4,
56 4.3BSD, C89.
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59 cbrt(3), cexp(3), exp10(3), exp2(3), sqrt(3)
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62 This page is part of release 3.25 of the Linux man-pages project. A
63 description of the project, and information about reporting bugs, can
64 be found at http://www.kernel.org/doc/man-pages/.
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68 2008-08-05 EXP(3)