1HYPOT(3) Linux Programmer's Manual HYPOT(3)
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6 hypot, hypotf, hypotl - Euclidean distance function
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9 #include <math.h>
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11 double hypot(double x, double y);
12 float hypotf(float x, float y);
13 long double hypotl(long double x, long double y);
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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 hypot():
20 _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE || _ISOC99_SOURCE ||
21 _POSIX_C_SOURCE >= 200112L;
22 or cc -std=c99
23 hypotf(), hypotl():
24 _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 ||
25 _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
26 or cc -std=c99
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29 The hypot() function returns sqrt(x*x+y*y). This is the length of the
30 hypotenuse of a right-angled triangle with sides of length x and y, or
31 the distance of the point (x,y) from the origin.
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33 The calculation is performed without undue overflow or underflow during
34 the intermediate steps of the calculation.
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37 On success, these functions return the length of a right-angled trianā
38 gle with sides of length x and y.
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40 If x or y is an infinity, positive infinity is returned.
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42 If x or y is a NaN, and the other argument is not an infinity, a NaN is
43 returned.
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45 If the result overflows, a range error occurs, and the functions return
46 HUGE_VAL, HUGE_VALF, or HUGE_VALL, respectively.
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48 If both arguments are subnormal, and the result is subnormal, a range
49 error occurs, and the correct result is returned.
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52 See math_error(7) for information on how to determine whether an error
53 has occurred when calling these functions.
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55 The following errors can occur:
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57 Range error: result overflow
58 errno is set to ERANGE. An overflow floating-point exception
59 (FE_OVERFLOW) is raised.
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61 Range error: result underflow
62 An underflow floating-point exception (FE_UNDERFLOW) is raised.
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64 These functions do not set errno for this case.
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67 C99, POSIX.1-2001. The variant returning double also conforms to SVr4,
68 4.3BSD.
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71 cabs(3), sqrt(3)
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74 This page is part of release 3.53 of the Linux man-pages project. A
75 description of the project, and information about reporting bugs, can
76 be found at http://www.kernel.org/doc/man-pages/.
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80 2010-09-20 HYPOT(3)