1TAN(3) Linux Programmer's Manual TAN(3)
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6 tan, tanf, tanl - tangent function
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9 #include <math.h>
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11 double tan(double x);
12 float tanf(float x);
13 long double tanl(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 tanf(), tanl():
20 _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 ||
21 _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
22 or cc -std=c99
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25 The tan() function returns the tangent of x, where x is given in radi‐
26 ans.
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29 On success, these functions return the tangent 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 or negative infinity, a domain error occurs,
34 and a NaN is returned.
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36 If the correct result would overflow, a range error occurs, and the
37 functions return HUGE_VAL, HUGE_VALF, or HUGE_VALL, respectively, with
38 the mathematically correct sign.
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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 Domain error: x is an infinity
47 errno is set to EDOM (but see BUGS). An invalid floating-point
48 exception (FE_INVALID) is raised.
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50 Range error: result overflow
51 An overflow floating-point exception (FE_OVERFLOW) is raised.
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54 C99, POSIX.1-2001. The variant returning double also conforms to SVr4,
55 4.3BSD, C89.
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58 Before version 2.10, the glibc implementation did not set errno to EDOM
59 when a domain error occurred.
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62 acos(3), asin(3), atan(3), atan2(3), cos(3), ctan(3), sin(3)
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65 This page is part of release 3.53 of the Linux man-pages project. A
66 description of the project, and information about reporting bugs, can
67 be found at http://www.kernel.org/doc/man-pages/.
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71 2010-09-11 TAN(3)