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  94  * |tan(x) - (x+t1*x^3+...+t6*x^13)|
  95  * |------------------------------ | <= 2^-59.73 for |x|<0.15625
  96  * |                x              |
  97  */
  98 t1      =  3.333333333333333333333333333333423342490e-0001L,
  99 t2      =  1.333333333333333333333333333093838744537e-0001L,
 100 t3      =  5.396825396825396825396827906318682662250e-0002L,
 101 t4      =  2.186948853615520282185576976994418486911e-0002L,
 102 t5      =  8.863235529902196573354554519991152936246e-0003L,
 103 t6      =  3.592128036572480064652191427543994878790e-0003L,
 104 t7      =  1.455834387051455257856833807581901305474e-0003L,
 105 t8      =  5.900274409318599857829983256201725587477e-0004L,
 106 t9      =  2.391291152117265181501116961901122362937e-0004L,
 107 t10     =  9.691533169382729742394024173194981882375e-0005L,
 108 t11     =  3.927994733186415603228178184225780859951e-0005L,
 109 t12     =  1.588300018848323824227640064883334101288e-0005L,
 110 t13     =  6.916271223396808311166202285131722231723e-0006L;
 111 /* INDENT ON */
 112 long double
 113 __k_tanl(long double x, long double y, int k) {
 114         long double a, t, z, w, s, c;
 115         int *pt = (int *) &t, *px = (int *) &x;
 116         int i, j, hx, ix;
 117 
 118         t = 1.0;
 119 #if defined(_BIG_ENDIAN)
 120         hx = px[0];
 121 #else
 122         XTOI(px, hx);


 123 #endif
 124         ix = hx & 0x7fffffff;
 125         if (ix < 0x3ffc4000) {
 126                 if (ix < 0x3fc60000) {
 127                         if ((i = (int) x) == 0) /* generate inexact */
 128                                 w = x;
 129                 } else {
 130                         z = x * x;
 131                         if (ix < 0x3ff30000) /* 2**-12 */
 132                                 t = z * (t1 + z * (t2 + z * (t3 + z * t4)));
 133                         else
 134                                 t = z * (t1 + z * (t2 + z * (t3 + z * (t4 +
 135                                         z * (t5 + z * (t6 + z * (t7 + z *
 136                                         (t8 + z * (t9 + z * (t10 + z * (t11 +
 137                                         z * (t12 + z * t13))))))))))));
 138                         t = y + x * t;
 139                         w = x + t;
 140                 }
 141                 return (k == 0 ? w : -one / w);
 142         }
 143         j = (ix + 0x400) & 0x7ffff800;
 144         i = (j - 0x3ffc4000) >> 11;
 145 #if defined(_BIG_ENDIAN)
 146         pt[0] = j;
 147 #else
 148         ITOX(j, pt);


 149 #endif
 150         if (hx > 0)
 151                 x = y - (t - x);
 152         else
 153                 x = (-y) - (t + x);
 154         a = _TBL_tanl_hi[i];
 155         z = x * x;
 156         /* cos(x)-1 */
 157         t = z * (qq1 + z * (qq2 + z * (qq3 + z * (qq4 + z * qq5))));
 158         /* sin(x) */
 159         s = x * (one + z * (pp1 + z * (pp2 + z * (pp3 + z * (pp4 + z *
 160                 pp5)))));
 161         if (k == 0) {
 162                 w = a * s;
 163                 t = _TBL_tanl_lo[i] + (s + a * w) / (one - (w - t));
 164                 return (hx < 0 ? -a - t : a + t);
 165         } else {
 166                 w = s + a * t;
 167                 c = w + _TBL_tanl_lo[i];
 168                 z = (one - (a * s - t));


  94  * |tan(x) - (x+t1*x^3+...+t6*x^13)|
  95  * |------------------------------ | <= 2^-59.73 for |x|<0.15625
  96  * |                x              |
  97  */
  98 t1      =  3.333333333333333333333333333333423342490e-0001L,
  99 t2      =  1.333333333333333333333333333093838744537e-0001L,
 100 t3      =  5.396825396825396825396827906318682662250e-0002L,
 101 t4      =  2.186948853615520282185576976994418486911e-0002L,
 102 t5      =  8.863235529902196573354554519991152936246e-0003L,
 103 t6      =  3.592128036572480064652191427543994878790e-0003L,
 104 t7      =  1.455834387051455257856833807581901305474e-0003L,
 105 t8      =  5.900274409318599857829983256201725587477e-0004L,
 106 t9      =  2.391291152117265181501116961901122362937e-0004L,
 107 t10     =  9.691533169382729742394024173194981882375e-0005L,
 108 t11     =  3.927994733186415603228178184225780859951e-0005L,
 109 t12     =  1.588300018848323824227640064883334101288e-0005L,
 110 t13     =  6.916271223396808311166202285131722231723e-0006L;
 111 /* INDENT ON */
 112 long double
 113 __k_tanl(long double x, long double y, int k) {
 114         long double a, t, z, w = 0.0, s, c;
 115         int *pt = (int *) &t, *px = (int *) &x;
 116         int i, j, hx, ix;
 117 
 118         t = 1.0;
 119 #if defined(__i386) || defined(__amd64)


 120         XTOI(px, hx);
 121 #else
 122         hx = px[0];
 123 #endif
 124         ix = hx & 0x7fffffff;
 125         if (ix < 0x3ffc4000) {
 126                 if (ix < 0x3fc60000) {
 127                         if ((i = (int) x) == 0) /* generate inexact */
 128                                 w = x;
 129                 } else {
 130                         z = x * x;
 131                         if (ix < 0x3ff30000) /* 2**-12 */
 132                                 t = z * (t1 + z * (t2 + z * (t3 + z * t4)));
 133                         else
 134                                 t = z * (t1 + z * (t2 + z * (t3 + z * (t4 +
 135                                         z * (t5 + z * (t6 + z * (t7 + z *
 136                                         (t8 + z * (t9 + z * (t10 + z * (t11 +
 137                                         z * (t12 + z * t13))))))))))));
 138                         t = y + x * t;
 139                         w = x + t;
 140                 }
 141                 return (k == 0 ? w : -one / w);
 142         }
 143         j = (ix + 0x400) & 0x7ffff800;
 144         i = (j - 0x3ffc4000) >> 11;
 145 #if defined(__i386) || defined(__amd64)


 146         ITOX(j, pt);
 147 #else
 148         pt[0] = j;
 149 #endif
 150         if (hx > 0)
 151                 x = y - (t - x);
 152         else
 153                 x = (-y) - (t + x);
 154         a = _TBL_tanl_hi[i];
 155         z = x * x;
 156         /* cos(x)-1 */
 157         t = z * (qq1 + z * (qq2 + z * (qq3 + z * (qq4 + z * qq5))));
 158         /* sin(x) */
 159         s = x * (one + z * (pp1 + z * (pp2 + z * (pp3 + z * (pp4 + z *
 160                 pp5)))));
 161         if (k == 0) {
 162                 w = a * s;
 163                 t = _TBL_tanl_lo[i] + (s + a * w) / (one - (w - t));
 164                 return (hx < 0 ? -a - t : a + t);
 165         } else {
 166                 w = s + a * t;
 167                 c = w + _TBL_tanl_lo[i];
 168                 z = (one - (a * s - t));