Changes between Version 1 and Version 3 of Ticket #15710
 Timestamp:
 01/23/14 11:24:39 (8 years ago)
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Ticket #15710

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Summary
changed from
sage hangs in division in cyclotomic field
toSage hangs in division of rational functions over cyclotomic field

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Summary
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Ticket #15710 – Description
v1 v3 1 1 From the [https://spreadsheets.google.com/pub?key=pCwvGVwSMxTzT6E2xNdo5fA google notebook bug reports] 2 2 3 Th e computation of b below hangs and cannot be interrupted.3 This hangs and cannot be interrupted: 4 4 {{{ 5 q=49 6 F.<E>=CyclotomicField(q) 7 G = F['z,w'].fraction_field() 8 [z,w]=G.gens() 9 10 denom = (EE^22)*(EE^27) 11 print denom 12 print 13 14 recip=1/denom 15 print recip 16 print 17 18 a=w*recip 19 print a 20 print 21 22 b=w/denom 23 print b 24 print 25 5 sage: F.<a>=CyclotomicField(49); G = F['z,w'].fraction_field(); 1/G(a^28 + a^23  1) 26 6 }}} 27 7 28 The attempt to evaluate b=w/denom hangs. But the reciprocal of the denominator is not complicated: Sage has no trouble evaluating recip=1/denom and then a=w*recip. 29 30 Note that z is not involved in this computation, just in the definition in the field of rational functions. 8 The problem is likely a bug in Singular.