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authorJulian Weigt <juw@posteo.de>2026-01-19 16:13:26 +0100
committerJulian Weigt <juw@posteo.de>2026-02-04 15:56:58 +0100
commit880bafc7c78f4c406bd579b551451cb13342820b (patch)
tree620031ca4b94f50a587efaf2a70876473e3ffc8a /double-error.c
parent96306e5ceb254cecd596a98fe9393d00f1039027 (diff)
In double-error replace double by typedef.
Diffstat (limited to 'double-error.c')
-rw-r--r--double-error.c35
1 files changed, 19 insertions, 16 deletions
diff --git a/double-error.c b/double-error.c
index 8df0974..63c820f 100644
--- a/double-error.c
+++ b/double-error.c
@@ -4,13 +4,16 @@
#include <float.h>
#include <stdbool.h>
+typedef double vtype;
+typedef double etype;
#define EPS 2*DBL_EPSILON
+#define MIN 2*DBL_MIN
-typedef struct {double v; double e;} double_error;
+typedef struct {vtype v; etype e;} double_error;
double_error int_to_valuetype(int i){
double_error de;
- de.v = (double) i;
+ de.v = (vtype) i;
if(abs(i) < 9999999) de.e = 0.0;
else de.e = EPS*abs(i);
return de;
@@ -30,7 +33,7 @@ bool exptype_is_infinite(double_error d){ return d.v == INFINITY; }
double_error sum(double_error de1, double_error de2){
double_error de;
de.v = de1.v + de2.v;
- de.e = de1.e + de2.e + ( fabs(de1.v) + fabs(de2.v) + de1.e + de2.e )*EPS + DBL_MIN;
+ de.e = de1.e + de2.e + ( fabs(de1.v) + fabs(de2.v) + de1.e + de2.e )*EPS + MIN;
return de;
}
@@ -42,11 +45,11 @@ double_error difference(double_error de1, double_error de2){
}
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;
+ return de1.v-de1.e > de2.v+de2.e + EPS*(fabs(de1.v)+fabs(de1.e)+fabs(de2.v)+fabs(de2.e)) + 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;
+ return de1.v+de1.e + EPS*(fabs(de1.v)+fabs(de1.e)+fabs(de2.v)+fabs(de2.e)) + MIN > de2.v-de2.e;
}
double_error maximum(double_error de1, double_error de2){
@@ -65,11 +68,11 @@ double_error maximum(double_error de1, double_error de2){
double_error product(double_error de1, double_error de2){
double_error de;
de.v = de1.v * de2.v;
- double p12 = fabs(de1.v)*de2.e*(1+EPS) + DBL_MIN;
- double p21 = fabs(de2.v)*de1.e*(1+EPS) + DBL_MIN;
- double p22 = de1.e*de2.e*(1+EPS) + DBL_MIN;
- double s = (p12 + p21 + p22)*(1+2*EPS);
- de.e = s + ( fabs(de.v) + s )*EPS + DBL_MIN;
+ vtype p12 = fabs(de1.v)*de2.e*(1+EPS) + MIN;
+ vtype p21 = fabs(de2.v)*de1.e*(1+EPS) + MIN;
+ vtype p22 = de1.e*de2.e*(1+EPS) + MIN;
+ etype s = (p12 + p21 + p22)*(1+2*EPS);
+ de.e = s + ( fabs(de.v) + s )*EPS + MIN;
return de;
}
@@ -77,7 +80,7 @@ double_error ratio(double_error de1, double_error de2){
double_error de2i;
de2i.v = 1/de2.v;
if(de2.e > fabs(de2.v)/2) de2i.e = INFINITY;
- else de2i.e = 2*de2.e/(de2.v*de2.v) + fabs(de2i.v)*EPS + DBL_MIN; //2* is extra margin in case de2.e is near de2.v/2
+ else de2i.e = 2*de2.e/(de2.v*de2.v) + fabs(de2i.v)*EPS + MIN; //2* is extra margin in case de2.e is near de2.v/2
return product(de1,de2i);
}
@@ -92,11 +95,11 @@ double_error absolute(double_error de){
double_error power(double_error de, double_error p) {
double_error dep;
dep.v = pow(de.v,p.v);
- double dmin = (de.v - de.e)*(1-EPS);
- double dmax = (de.v + de.e)*(1+EPS);
- double pmin = (p.v - p.e)*(1-EPS);
- double pmax = (p.v + p.e)*(1+EPS);
- double rmin,rmax;
+ vtype dmin = (de.v - de.e)*(1-EPS);
+ vtype dmax = (de.v + de.e)*(1+EPS);
+ vtype pmin = (p.v - p.e)*(1-EPS);
+ vtype pmax = (p.v + p.e)*(1+EPS);
+ vtype rmin,rmax;
if(dmin >= 1){
rmin = pow(dmin,pmin);
rmax = pow(dmax,pmax);