BOOST_CHECK_CLOSE(0, smallnumber) fails about test HOT 4 CLOSED

Hi,

There were many bug fixes since 1.60 (see here for more details).

Would you please try again with the latest version of Boost?

from test.

Sorry for the late investigation. It turns out that you cannot use BOOST_CHECK_CLOSE to compare to the value 0, as it would use the algorithm described here.

You have 2 options:

• either use BOOST_CHECK_SMALL(-4.37113883e-08, 1.) (note . in the 1.)
• or use BOOST_TEST(-4.37113883e-08 == 0, 1. % tt::tolerance()) (for percentage tolerance)

Hope that helps!

from test.

Thank you @raffienficiaud
I have retried with 1.69 and the same behavior.
Could nt find a better perf than writing my own CHECK macro doing :
CHECK_CLOSE(result, ref)
if (result == 0 || ref == 0)
BOOST_CHECK_SMALL(result - ref, 0.01f);
else
BOOST_CHECK_CLOSE(result, ref, 0.01f);

Mathematically speaking, it is legit to wonder if 0.0000001 is "close" to 0 (within a range).
Should nt it be illogic to expect BOOST_CHECK_CLOSE() to work even if left or right are 0 ?

from test.

If you look at the equations for comparison here, then only equation (1) can work when one of the arguments u or v is 0. This is why there exists BOOST_CHECK_SMALL and BOOST_CHECK_CLOSE.

On the other hand, this is done automatically with BOOST_TEST if

• one of the arguments is floating point (since 1.70, otherwise the two arguments should be floating points)
• and one of the argument is zero,

so you should not be needing to write your own logic.

from test.