Introduce is_greater_certainly and is_greater_possibly to make more robust the printing and finding of records.

Start reorganizing to allow eventual printing of all records.

1 files changed, 16 insertions, 12 deletions

diff --git a/double-error.c b/double-error.c
index e166ec0..16c7e1e 100644
--- a/double-error.c
+++ b/double-error.c
@@ -41,21 +41,25 @@ double_error difference(double_error de1, double_error de2){
 	return sum(de1,de2m);
 }
 
-bool is_greater(double_error de1, double_error de2){ return ((1+EPS)*(de1.v+de1.e) > de2.v-de2.e); }
+bool is_greater_certainly(double_error de1, double_error de2){
+	return de1.v-de1.e > de2.v+de2.e + EPS*(fabs(de1.v)+fabs(de1.e)+fabs(de2.v)+fabs(de2.e)) + DBL_MIN;
+}
+
+bool is_greater_possibly(double_error de1, double_error de2){
+	return de1.v+de1.e + EPS*(fabs(de1.v)+fabs(de1.e)+fabs(de2.v)+fabs(de2.e)) + DBL_MIN > de2.v-de2.e;
+}
 
 double_error maximum(double_error de1, double_error de2){
-	double_error de;
-	double max1 = de1.v + de1.e;
-	double max2 = de2.v + de2.e;
-	if( max1 >= max2 ){
-		de.v = de1.v;
-		de.e = de1.e + max1*EPS + DBL_MIN;
-	} else {
-		de.v = de2.v;
-		de.e = de2.e + max2*EPS + DBL_MIN;
+	if(is_greater_certainly(de1,de2)) return de1;
+	else if(is_greater_certainly(de2,de1)) return de2;
+	else{
+		double_error de;
+		if( de1.v >= de2.v ) de.v = de1.v;
+		else de.v = de2.v;
+		if( de1.e >= de2.e ) de.e = de1.e;
+		else de.e = de2.e;
+		return de;
 	}
-
-	return de;
 }
 
 double_error product(double_error de1, double_error de2){