Changeset 3577 in Sophya for trunk/SophyaLib/SysTools

Timestamp:

Feb 20, 2009, 12:17:14 AM (17 years ago)

Author:

ansari

Message:

amelioration format conversion double->string pour eviter perte de precision lors des evaluations avec l'interpreteur (Commander) - Reza 19/02/2008

File:

• trunk/SophyaLib/SysTools/commander.cc (modified) (4 diffs)

trunk/SophyaLib/SysTools/commander.cc

@@ -17 +17 @@
 
 namespace SOPHYA {
+
+//--------------------------------------------------
+// Pour ecrire une valeur double sous forme de string 
+// sans perte de precision, et si possible de maniere 
+// lisible (%g, sinon %.17e)  
+static char cval_strbuff_[64];
+char * cval_dble2str(double v)
+{
+  char* str1 = cval_strbuff_;  
+  sprintf(str1,"%g",v);
+  char* str2 = cval_strbuff_+32;       
+  sprintf(str2,"%.17e",v);
+  double x1 = atof(str1);
+  double x2 = atof(str2);
+  double fx = fabs(v);
+  if (fx>0. && fabs(x2-x1)/fx>1e-12)  return str2;
+  else return str1;
+}
+//--------------------------------------------------
 
 // Differents code de retour specifiques 
@@ -219 +238 @@
       break;
       }
-    sprintf(buff, "%g", f);
-    string lvv = buff;
+    string lvv = cval_dble2str(f);
     rcc = ExecuteOnce(lvv);
     if (rcc == CMD_BREAKEXE_RC)  return rcc;
@@ -1057 +1075 @@
         res = cex.Value();
       }
-      char cbuff[64];
-      sprintf(cbuff,"%g",res);
-      string vv = cbuff;
+      string vv =  cval_dble2str(res);
       SetVariable(kw, vv);
     }
@@ -1805 +1821 @@
     RPNExpressionEvaluator rpn(tokens, 1);
     double res = rpn.Value();
-    char cbuff[64];
-    sprintf(cbuff,"%g",res);
-    string vv = cbuff;
+    string vv = cval_dble2str(res);
     SetVariable(tokens[0],vv);
     return 0;