1REMQUO(P)                  POSIX Programmer's Manual                 REMQUO(P)
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NAME

6       remquo, remquof, remquol - remainder functions
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SYNOPSIS

9       #include <math.h>
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11       double remquo(double x, double y, int *quo);
12       float remquof(float x, float y, int *quo);
13       long double remquol(long double x, long double y, int *quo);
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DESCRIPTION

17       The remquo(), remquof(), and remquol() functions shall compute the same
18       remainder as the remainder(), remainderf(), and remainderl() functions,
19       respectively. In the object pointed to by quo, they store a value whose
20       sign is the sign of x/ y and whose magnitude is congruent  modulo  2**n
21       to the magnitude of the integral quotient of x/ y, where n is an imple‐
22       mentation-defined integer greater than or equal to 3.
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24       An application wishing to check for error situations should  set  errno
25       to  zero  and  call  feclearexcept(FE_ALL_EXCEPT)  before calling these
26       functions.  On return, if errno is non-zero or  fetestexcept(FE_INVALID
27       |  FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is non-zero, an error has
28       occurred.
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RETURN VALUE

31       These functions shall return x REM y.
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33       If x or y is NaN, a NaN shall be returned.
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35       If x is ±Inf or y is zero and the other argument is non-NaN,  a  domain
36       error  shall  occur, and either a NaN (if supported), or an implementa‐
37       tion-defined value shall be returned.
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ERRORS

40       These functions shall fail if:
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42       Domain Error
43              The x argument is ±Inf, or the y argument is ±0  and  the  other
44              argument is non-NaN.
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46       If  the integer expression (math_errhandling & MATH_ERRNO) is non-zero,
47       then  errno  shall  be  set  to  [EDOM].  If  the  integer   expression
48       (math_errhandling  &  MATH_ERREXCEPT)  is  non-zero,  then  the invalid
49       floating-point exception shall be raised.
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52       The following sections are informative.
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EXAMPLES

55       None.
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APPLICATION USAGE

58       On  error,  the  expressions  (math_errhandling   &   MATH_ERRNO)   and
59       (math_errhandling  & MATH_ERREXCEPT) are independent of each other, but
60       at least one of them must be non-zero.
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RATIONALE

63       These functions are intended for implementing argument reductions which
64       can exploit a few low-order bits of the quotient. Note that x may be so
65       large in magnitude relative to y that an exact  representation  of  the
66       quotient is not practical.
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FUTURE DIRECTIONS

69       None.
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SEE ALSO

72       feclearexcept()  ,  fetestexcept() , remainder() , the Base Definitions
73       volume of IEEE Std 1003.1-2001, Section 4.18, Treatment of Error Condi‐
74       tions for Mathematical Functions, <math.h>
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77       Portions  of  this text are reprinted and reproduced in electronic form
78       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
79       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
80       Specifications Issue 6, Copyright (C) 2001-2003  by  the  Institute  of
81       Electrical  and  Electronics  Engineers, Inc and The Open Group. In the
82       event of any discrepancy between this version and the original IEEE and
83       The  Open Group Standard, the original IEEE and The Open Group Standard
84       is the referee document. The original Standard can be  obtained  online
85       at http://www.opengroup.org/unix/online.html .
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89IEEE/The Open Group                  2003                            REMQUO(P)
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