result of pow2_x is never more precise than double 3 results were exact to double the precision 20 largest ulp errors (stored in a double) 0.50174 ulp for pow2_x(-1019.4477483470932) = 1.3051148625743324e-307) 0.50134 ulp for pow2_x(-1019.221324715983) = 1.5268945329574641e-307) 0.50130 ulp for pow2_x(494.79476970000286) = 8.8729365795050977e+148) 0.50122 ulp for pow2_x(1015.9780960839786) = 6.9164279771611274e+305) 0.50116 ulp for pow2_x(1016.6226593800319) = 1.0812216793851632e+306) 0.50086 ulp for pow2_x(331.71619008000607) = 7.1865964982636904e+99) 0.50085 ulp for pow2_x(-1013.0724841691289) = 1.0834140997310295e-305) 0.50084 ulp for pow2_x(-9.0965589942999614) = 0.0018266817312379948) 0.50082 ulp for pow2_x(-9.0520129452002642) = 0.0018839639245153972) 0.50069 ulp for pow2_x(447.92829894002352) = 6.9159825320490278e+134) 0.50065 ulp for pow2_x(5.5990533549998824) = 48.471114675739003) 0.50061 ulp for pow2_x(1016.6574143825932) = 1.1075849435715789e+306) 0.50060 ulp for pow2_x(1020.7274856013461) = 1.8603324632649233e+307) 0.50051 ulp for pow2_x(331.71619008054017) = 7.1865965009242435e+99) 0.50051 ulp for pow2_x(8.530270633000038) = 369.71522187337587) 0.50049 ulp for pow2_x(368.17496363999669) = 6.7874666410059797e+110) 0.50049 ulp for pow2_x(490.43178948059028) = 4.312007035932307e+147) 0.50049 ulp for pow2_x(1021.1893671905309) = 2.5623047251446425e+307) 0.50048 ulp for pow2_x(-1020.7202614525133) = 5.4023674596477259e-308) 0.50048 ulp for pow2_x(9.7764443580006226) = 877.00688472006925) pow2_x14670.50174-1019.44774834709321.3051148625743324e-307