Hi Gregory,
In Origin 8.0, this constant is not available yet. We are very sorry for that. However, it can be accessed in current version, Origin 8.1 SR3. If you are interested, you can download a demo from this page to have a try.
For a workaround, you can define this constant by yourself. I have run the following code in Origin 8.1 SR3 to get the value.
#include <OC_nag8.h>
void testDBL_EPSILON()
{
double dDBL_EPSILON = X02AJC;
printf("d=%16.15e\n", dDBL_EPSILON);
}
And the value is 1.110223024625157e-016.
Penn