As it happens, I am also just now using this to check my collection of high accuracy man constants and I am similarly confused. If I want to check that two values differ by not more than just one binary ULP (least significant bit), is the BOOST_CHECK_CLOSE tolerance numeric_limits<double>::epsilon() * 100.? *100. because tolerance is in percent - sniff ;-) Thanks Paul Paul A Bristow Prizet Farmhouse, Kendal, Cumbria UK LA8 8AB +44 1539 561830 +44 7714 330204 mailto: pbristow@hetp.u-net.com | -----Original Message----- | From: boost-bounces@lists.boost.org | [mailto:boost-bounces@lists.boost.org] On Behalf Of Jody Hagins | Sent: 25 May 2005 17:06 | To: boost@lists.boost.org | Subject: [boost] [test] Confusion about BOOST_CHECK_CLOSE | | | I have re-read everything I can find about BOOST_CHECK_CLOSE, and the | doc on floating point comparison algorithms (i.e.close_at_tolerance). | | However, I am still confused about how to use | BOOST_CHECK_CLOSE. Could | we have some clear examples of comparisons that pass/fail | with different | tolerance settings, and some explanation as to how changing the | tolerance may affect the test? | | Currently, I have a test, using BOOST_CHECK_CLOSE() which passes, no | matter how big/small I set the tolerance; yet the values are | different. | | Thanks! | | _______________________________________________ | Unsubscribe & other changes: | http://lists.boost.org/mailman/listinfo.cgi/boost |