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-rw-r--r--newlib/libm/mathfp/sf_atangent.c140
1 files changed, 0 insertions, 140 deletions
diff --git a/newlib/libm/mathfp/sf_atangent.c b/newlib/libm/mathfp/sf_atangent.c
deleted file mode 100644
index 55a9006..0000000
--- a/newlib/libm/mathfp/sf_atangent.c
+++ /dev/null
@@ -1,140 +0,0 @@
-
-/* @(#)z_atangentf.c 1.0 98/08/13 */
-/******************************************************************
- * The following routines are coded directly from the algorithms
- * and coefficients given in "Software Manual for the Elementary
- * Functions" by William J. Cody, Jr. and William Waite, Prentice
- * Hall, 1980.
- ******************************************************************/
-/******************************************************************
- * Arctangent
- *
- * Input:
- * x - floating point value
- *
- * Output:
- * arctangent of x
- *
- * Description:
- * This routine calculates arctangents.
- *
- *****************************************************************/
-
-#include <float.h>
-#include "fdlibm.h"
-#include "zmath.h"
-
-static const float ROOT3 = 1.732050807;
-static const float a[] = { 0.0, 0.523598775, 1.570796326,
- 1.047197551 };
-static const float q[] = { 0.1412500740e+1 };
-static const float p[] = { -0.4708325141, -0.5090958253e-1 };
-
-float
-_DEFUN (atangentf, (float, float, float, int),
- float x _AND
- float v _AND
- float u _AND
- int arctan2)
-{
- float f, g, R, P, Q, A, res;
- int N;
- int branch = 0;
- int expv, expu;
-
- /* Preparation for calculating arctan2. */
- if (arctan2)
- {
- if (u == 0.0)
- if (v == 0.0)
- {
- errno = ERANGE;
- return (z_notanum_f.f);
- }
- else
- {
- branch = 1;
- res = __PI_OVER_TWO;
- }
-
- if (!branch)
- {
- int e;
- /* Get the exponent values of the inputs. */
- g = frexpf (v, &expv);
- g = frexpf (u, &expu);
-
- /* See if a divide will overflow. */
- e = expv - expu;
- if (e > FLT_MAX_EXP)
- {
- branch = 1;
- res = __PI_OVER_TWO;
- }
-
- /* Also check for underflow. */
- else if (e < FLT_MIN_EXP)
- {
- branch = 2;
- res = 0.0;
- }
- }
- }
-
- if (!branch)
- {
- if (arctan2)
- f = fabsf (v / u);
- else
- f = fabsf (x);
-
- if (f > 1.0)
- {
- f = 1.0 / f;
- N = 2;
- }
- else
- N = 0;
-
- if (f > (2.0 - ROOT3))
- {
- A = ROOT3 - 1.0;
- f = (((A * f - 0.5) - 0.5) + f) / (ROOT3 + f);
- N++;
- }
-
- /* Check for values that are too small. */
- if (-z_rooteps_f < f && f < z_rooteps_f)
- res = f;
-
- /* Calculate the Taylor series. */
- else
- {
- g = f * f;
- P = (p[1] * g + p[0]) * g;
- Q = g + q[0];
- R = P / Q;
-
- res = f + f * R;
- }
-
- if (N > 1)
- res = -res;
-
- res += a[N];
- }
-
- if (arctan2)
- {
- if (u < 0.0 || branch == 2)
- res = __PI - res;
- if (v < 0.0 || branch == 1)
- res = -res;
- }
- else if (x < 0.0)
- {
- res = -res;
- }
-
- return (res);
-}