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serge |
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/* |
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* ==================================================== |
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
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* |
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* Developed at SunPro, a Sun Microsystems, Inc. business. |
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* Permission to use, copy, modify, and distribute this |
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* software is freely granted, provided that this notice |
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* is preserved. |
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* ==================================================== |
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*/ |
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FUNCTION |
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<>, <>---distance from origin |
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INDEX |
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hypot |
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INDEX |
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hypotf |
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#include |
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double hypot(double <[x]>, double <[y]>); |
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float hypotf(float <[x]>, float <[y]>); |
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double hypot(<[x]>, <[y]>) |
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double <[x]>, <[y]>; |
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float <[x]>, <[y]>; |
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<> calculates the Euclidean distance |
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@tex |
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$\sqrt{x^2+y^2}$ |
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@end tex |
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@ifnottex |
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<*<[x]> + <[y]>*<[y]>)>> |
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@end ifnottex |
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between the origin (0,0) and a point represented by the |
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Cartesian coordinates (<[x]>,<[y]>). <> differs only |
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in the type of its arguments and result. |
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Normally, the distance value is returned. On overflow, |
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<> returns <> and sets <> to |
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<>. |
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<> and <> are not ANSI C. */ |
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* wrapper hypot(x,y) |
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*/ |
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#include |
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double hypot(double x, double y)/* wrapper hypot */ |
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#else |
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double hypot(x,y) /* wrapper hypot */ |
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double x,y; |
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#endif |
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{ |
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#ifdef _IEEE_LIBM |
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return __ieee754_hypot(x,y); |
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#else |
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double z; |
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struct exception exc; |
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z = __ieee754_hypot(x,y); |
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if(_LIB_VERSION == _IEEE_) return z; |
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if((!finite(z))&&finite(x)&&finite(y)) { |
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/* hypot(finite,finite) overflow */ |
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#ifndef HUGE_VAL |
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#define HUGE_VAL inf |
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double inf = 0.0; |
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#endif |
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exc.type = OVERFLOW; |
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exc.name = "hypot"; |
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exc.err = 0; |
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exc.arg1 = x; |
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exc.arg2 = y; |
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if (_LIB_VERSION == _SVID_) |
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exc.retval = HUGE; |
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else |
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exc.retval = HUGE_VAL; |
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if (_LIB_VERSION == _POSIX_) |
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errno = ERANGE; |
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else if (!matherr(&exc)) { |
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errno = ERANGE; |
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} |
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if (exc.err != 0) |
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errno = exc.err; |
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return exc.retval; |
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} else |
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return z; |
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#endif |
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} |
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