4 ms·
Not entirely; it means the comparison was effectively between single-precision and double-precision logs from the C library.
by andrewf 16y ago
Not entirely; it means the comparison was effectively between single-precision and double-precision logs from the C library.
- mturmon 16y agoWere they not both calling the normal double-precision log function in libm? Sure, the linked article scans all the single-precision floats in a certain range to do the test, but the function eventually called (using that list of floats) is log in libm. In any event, no discrepancy is noted, so what was the point? Additionally, TFA does not make clear that there should be no errors in the computed function affecting more than the least sig bit. It uses absolute errors (up to 50 e-17) rather than looking at the relative error (or ULP, in the jargon). It seems like a mess. Here's a link with much more useful information: http://www.gnu.org/s/libc/manual/html_node/Errors-in-Math-Functions.html http://www.gnu.org/s/libc/manual/html_node/Errors-in-Math-Fu...