10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 
  22 /*
  23  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  24  */
  25 /*
  26  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  27  * Use is subject to license terms.
  28  */
  29 
  30 #pragma weak atanf = __atanf
  31 
  32 /* INDENT OFF */
  33 /*
  34  * float atanf(float x);
  35  * Table look-up algorithm
  36  * By K.C. Ng, March 9, 1989
  37  *
  38  * Algorithm.
  39  *
  40  * The algorithm is based on atan(x)=atan(y)+atan((x-y)/(1+x*y)).
  41  * We use poly1(x) to approximate atan(x) for x in [0,1/8] with
  42  * error (relative)
  43  *      |(atan(x)-poly1(x))/x|<= 2^-115.94   long double
  44  *      |(atan(x)-poly1(x))/x|<= 2^-58.85    double
  45  *      |(atan(x)-poly1(x))/x|<= 2^-25.53    float
  46  * and use poly2(x) to approximate atan(x) for x in [0,1/65] with
  47  * error (absolute)
  48  *      |atan(x)-poly2(x)|<= 2^-122.15               long double
  49  *      |atan(x)-poly2(x)|<= 2^-64.79                double
  50  *      |atan(x)-poly2(x)|<= 2^-35.36                float

  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 
  22 /*
  23  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  24  */
  25 /*
  26  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  27  * Use is subject to license terms.
  28  */
  29 
  30 #pragma weak __atanf = atanf
  31 
  32 /* INDENT OFF */
  33 /*
  34  * float atanf(float x);
  35  * Table look-up algorithm
  36  * By K.C. Ng, March 9, 1989
  37  *
  38  * Algorithm.
  39  *
  40  * The algorithm is based on atan(x)=atan(y)+atan((x-y)/(1+x*y)).
  41  * We use poly1(x) to approximate atan(x) for x in [0,1/8] with
  42  * error (relative)
  43  *      |(atan(x)-poly1(x))/x|<= 2^-115.94   long double
  44  *      |(atan(x)-poly1(x))/x|<= 2^-58.85    double
  45  *      |(atan(x)-poly1(x))/x|<= 2^-25.53    float
  46  * and use poly2(x) to approximate atan(x) for x in [0,1/65] with
  47  * error (absolute)
  48  *      |atan(x)-poly2(x)|<= 2^-122.15               long double
  49  *      |atan(x)-poly2(x)|<= 2^-64.79                double
  50  *      |atan(x)-poly2(x)|<= 2^-35.36                float