1SQRT(3) Linux Programmer's Manual SQRT(3)
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6 sqrt, sqrtf, sqrtl - square root function
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9 #include <math.h>
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11 double sqrt(double x);
12 float sqrtf(float x);
13 long double sqrtl(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 sqrtf(), sqrtl(): _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600
20 || _ISOC99_SOURCE; or cc -std=c99
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23 The sqrt() function returns the nonnegative square root of x.
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26 On success, these functions return the square root of x.
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28 If x is a NaN, a NaN is returned.
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30 If x is +0 (-0), +0 (-0) is returned.
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32 If x is positive infinity, positive infinity is returned.
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34 If x is less than -0, a domain error occurs, and a NaN is returned.
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37 See math_error(7) for information on how to determine whether an error
38 has occurred when calling these functions.
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40 The following errors can occur:
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42 Domain error: x less than -0
43 errno is set to EDOM. An invalid floating-point exception
44 (FE_INVALID) is raised.
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47 C99, POSIX.1-2001. The variant returning double also conforms to SVr4,
48 4.3BSD, C89.
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51 cbrt(3), csqrt(3), hypot(3)
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54 This page is part of release 3.25 of the Linux man-pages project. A
55 description of the project, and information about reporting bugs, can
56 be found at http://www.kernel.org/doc/man-pages/.
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60 2008-08-05 SQRT(3)