result of log is never more precise than double 1 results were exact to double the precision 20 largest ulp errors (stored in a double) 0.55045 ulp for log(397.391652719999797) = 5.98492232516636413) 0.54499 ulp for log(424.112110459999997) = 6.04999783174367245) 0.53945 ulp for log(401.01229047999982) = 5.99399207641294041) 0.53368 ulp for log(376.094201959999907) = 5.92983964913836914) 0.53057 ulp for log(416.244840379999516) = 6.03127364573434477) 0.52936 ulp for log(1.13314845306682743) = 0.125000000000000999) 0.52911 ulp for log(0.741966908100000544) = -0.298450635057265767) 0.52907 ulp for log(405.779366979999907) = 6.00580958080580096) 0.52894 ulp for log(466.053110759999697) = 6.14429959921936053) 0.52829 ulp for log(447.928298940000218) = 6.10463317259716831) 0.52820 ulp for log(494.794769700000131) = 6.20414306992891618) 0.52752 ulp for log(0.648630719799999422) = -0.432891722986613381) 0.52748 ulp for log(371.984589120000237) = 5.91885242631824759) 0.52713 ulp for log(0.00754871630000000012) = -4.8863777566674127) 0.52700 ulp for log(447.928298940003401) = 6.10463317259717542) 0.51763 ulp for log(416.244840379991388) = 6.03127364573432523) 0.51525 ulp for log(0.64863071980001541) = -0.432891722986588734) 0.51477 ulp for log(441.210825319999913) = 6.08952282316175086) 0.51323 ulp for log(328.152830119999066) = 5.79347944535305537) 0.51288 ulp for log(0.741966908099999101) = -0.298450635057267655)