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# define TGSOURCE "atan2.c"
#include <math.h>
#include "nonstd/tgmath.h"
#include "errno.h"
#include "nonstd/assert.h"
/** arc tangent **/
TYPE TGFN(atan2)(TYPE y, TYPE x)
{
ASSERT_NONZERO(x);
if (y == 0 && x == 0) {
errno = EDOM; /* ARGUMENT(y) and ARGUMENT(x) are both LITERAL(0)) */
return TGHUGE;
}
if (0) {
errno = ERANGE; /* The result cannot be represented */
/* RETURN_FAILURE(CONSTANT(HUGE_VAL), A range error occurred); */
return TGHUGE;
}
TYPE ret = TGFN(tan)(y / x);
/* FIXME: quadrant */
/* RETURN_SUCCESS(a value in range `[-PI(), +PI()]'); */
return ret;
}
/***
functions compute the principal value of the arc tangent of
ARGUMENT(y)/ARGUMENT(x), using the signs of both to place the return value in
the correct quadrant.
***/
/*
IMPLEMENTATION(The value returned on a domain error, CONSTANT(HUGE_VAL))
LINK(m)
*/
/*
STDC(1)
*/
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