id summary reporter owner description type status priority milestone component resolution keywords cc work_issues upstream reviewer author merged dependencies stopgaps 3354 Bug in power series sqrt robertwb somebody "{{{ sage: t = QQ[['t']].0 sage: sqrt(1+t) 1 + 1/2*t - 1/8*t^2 + 1/16*t^3 - 5/128*t^4 + 7/256*t^5 - 21/1024*t^6 + 33/2048*t^7 - 429/32768*t^8 + 715/65536*t^9 - 2431/262144*t^10 + 4199/524288*t^11 - 29393/4194304*t^12 + 52003/8388608*t^13 - 185725/33554432*t^14 + 334305/67108864*t^15 - 9694845/2147483648*t^16 + 17678835/4294967296*t^17 - 64822395/17179869184*t^18 + 119409675/34359738368*t^19 + O(t^20) sage: sqrt(2+t) ------------------------------------------------------------ Traceback (most recent call last): File """", line 1, in File ""/Users/robert/sage/current/local/lib/python2.5/site-packages/sage/calculus/calculus.py"", line 7664, in __call__ return x.sqrt(*args, **kwds) File ""power_series_ring_element.pyx"", line 1120, in sage.rings.power_series_ring_element.PowerSeries.sqrt (sage/rings/power_series_ring_element.c:7887) : power series does not have a square root since it has odd valuation. }}} Perhaps the error is just bad, but it should be able to compute this by extending to a field with sqrt(2). " defect new major sage-5.10 basic arithmetic