add some flags

git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@1433 280ebfd0-de03-0410-8827-d642c229c3f4

1 files changed, 82 insertions, 76 deletions

diff --git a/hypot.c b/hypot.c
index 4e9072d6a..4491c4e4e 100644
--- a/hypot.c
+++ b/hypot.c
@@ -43,94 +43,100 @@ mpfr_hypot (z, x,y, rnd_mode)
 #endif
 {
   int inexact;
+  /* Flag calcul exacte */
+  int not_exact=0;
 
-    /* particular cases */
+  /* particular cases */
 
-    if (MPFR_IS_NAN(x) || MPFR_IS_NAN(y))
-      {
-	MPFR_SET_NAN(z);
-	return 1;
-      }
+  if (MPFR_IS_NAN(x) || MPFR_IS_NAN(y))
+  {
+    MPFR_SET_NAN(z);
+    return 1;
+  }
 
-    MPFR_CLEAR_NAN(z);
+  MPFR_CLEAR_NAN(z);
 
-    if (MPFR_IS_INF(x) || MPFR_IS_INF(y))
-      {
-	MPFR_SET_INF(z);
-	if (MPFR_SIGN(z) < 0)
-	  MPFR_CHANGE_SIGN(z);
-	return 0;
-      }
+  if (MPFR_IS_INF(x) || MPFR_IS_INF(y))
+  {
+    MPFR_SET_INF(z);
+    if (MPFR_SIGN(z) < 0)
+      MPFR_CHANGE_SIGN(z);
+    return 0;
+  }
 
-    MPFR_CLEAR_INF(z);
+  MPFR_CLEAR_INF(z);
   
-    if(!MPFR_NOTZERO(x))
-      return mpfr_abs (z, y, rnd_mode);
-
-    if(!MPFR_NOTZERO(y))
-      return mpfr_abs (z, x, rnd_mode);
-
-    /* General case */
-
-    {
-      /* Declaration of the intermediary variable */
-      mpfr_t t, te,ti;       
-
-      /* Flag calcul exacte */
-      int not_exact=0;
-
-      /* Declaration of the size variable */
-      mp_prec_t Nx = MPFR_PREC(x);   /* Precision of input variable */
-      mp_prec_t Ny = MPFR_PREC(y);   /* Precision of input variable */
-      mp_prec_t Nz = MPFR_PREC(z);   /* Precision of input variable */
+  if(!MPFR_NOTZERO(x))
+    return mpfr_abs (z, y, rnd_mode);
+  
+  if(!MPFR_NOTZERO(y))
+    return mpfr_abs (z, x, rnd_mode);
+
+  /* General case */
+
+  {
+    /* Declaration of the intermediary variable */
+    mpfr_t t, te,ti;
+    /* Declaration of the size variable */
+    mp_prec_t Nx = MPFR_PREC(x);   /* Precision of input variable */
+    mp_prec_t Ny = MPFR_PREC(y);   /* Precision of input variable */
+    mp_prec_t Nz = MPFR_PREC(z);   /* Precision of input variable */
       
-      mp_prec_t Nt;   /* Precision of the intermediary variable */
-      long int err;  /* Precision of error */
+    int  Nt;   /* Precision of the intermediary variable */
+    long int err;  /* Precision of error */
       
-      /* compute the precision of intermediary variable */
-      Nt=MAX(MAX(Nx,Ny),Nz);
-
-      /* compute the size of intermediary variable -- see algorithms.ps */
-      Nt=Nt+2+_mpfr_ceil_log2(Nt);
-
-      /* initialise the intermediary variables */
-      mpfr_init(t);             
-      mpfr_init(te);             
-      mpfr_init(ti); 
-
-      /* Hypot */
-      do {
-        not_exact=0;
-        /* reactualisation of the precision */
-        mpfr_set_prec(t,Nt);             
-        mpfr_set_prec(te,Nt);             
-        mpfr_set_prec(ti,Nt);   
-
-        /* computations of hypot */
-        if(mpfr_mul(te,x,x,GMP_RNDN))         /* x^2 */
-          not_exact=1;
-
-        if(mpfr_mul(ti,y,y,GMP_RNDN))         /* y^2 */
-          not_exact=1;          
-
-        if(mpfr_add(t,te,ti,GMP_RNDD))        /*x^2+y^2*/
-          not_exact=1;
+    /* compute the precision of intermediary variable */
+    Nt=MAX(MAX(Nx,Ny),Nz);
+
+    /* compute the size of intermediary variable -- see algorithms.ps */
+    Nt=Nt+2+_mpfr_ceil_log2(Nt);
+
+    /* initialise the intermediary variables */
+    mpfr_init(t);             
+    mpfr_init(te);             
+    mpfr_init(ti); 
+
+    /* Hypot */
+    do {
+      not_exact=0;
+      /* reactualisation of the precision */
+      mpfr_set_prec(t,Nt);             
+      mpfr_set_prec(te,Nt);             
+      mpfr_set_prec(ti,Nt);   
+
+      /* computations of hypot */
+      if(mpfr_mul(te,x,x,GMP_RNDN))   /* x^2 */
+        not_exact=1;
+
+      if(mpfr_mul(ti,y,y,GMP_RNDN))   /* y^2 */
+        not_exact=1;          
+      
+      if(mpfr_add(t,te,ti,GMP_RNDD))  /*x^2+y^2*/
+        not_exact=1;
 
-        if(mpfr_sqrt(t,t,GMP_RNDN))           /* sqrt(x^2+y^2)*/
-          not_exact=1;
+      if(mpfr_sqrt(t,t,GMP_RNDN))     /* sqrt(x^2+y^2)*/
+        not_exact=1;
  
-        /* estimation of the error */
-        err=Nt-(2);
+      /* estimation of the error */
+      err=Nt-(2);
     
-        Nt += 10; 
+      Nt += 10; 
+      if(Nt<0)Nt=0;
+
+    } while ((err <0) || ((!mpfr_can_round(t,err,GMP_RNDN,rnd_mode,Nz)) && not_exact));
+
+    inexact = mpfr_set (z, t, rnd_mode);
+    mpfr_clear(t);
+    mpfr_clear(ti);
+    mpfr_clear(te);
 
-      } while ((err <0) || ((!mpfr_can_round(t,err,GMP_RNDN,rnd_mode,Nz)) && not_exact));
+  }
 
-      inexact = mpfr_set (z, t, rnd_mode);
-      mpfr_clear(t);
-      mpfr_clear(ti);
-      mpfr_clear(te);
+  if (not_exact == 0 && inexact == 0)
+    return 0;
+        
+  if (not_exact != 0 && inexact == 0)
+    return 1;
 
-    }
-    return inexact;
+  return inexact;
 }