Why are the return values of these doubles -1.#IND?
I have :
double score = cvMatchContourTrees( CT1, CT2, CV_CONTOUR_TREES_MATCH_I1, 0.0 );
cout<<score<<endl;
There are values returned as -1.#IND. Other than that, the positive values are normal, like 1.34543.
Why does this happen? How do I solve it?
Solution 1:
As Frederic says, it's the result of a 'Not a Number' being formatted by an application built with visual studio on windows. John D Cook has an excellent reference:
Windows displays a NaN as -1.#IND ("IND" for "indeterminate") while Linux displays nan.
...
In short, if you get 1.#INF or inf, look for overflow or division by zero. If you get 1.#IND or nan, look for illegal operations.
Watch out for truncations if you do any sort of formatting with your string; I've encountered related issues when handling these sorts of errors myself.
Solution 2:
std::cout << (0/0.f);
// Output: -1.#IND
It's NaN.