conversion of bigoh to symbolic

[dkrenn]

sage: P.<p> = ZZ[[]]
sage: a = 1/(1+p)
sage: o = a - a.truncate()
sage: o
O(p^20)
sage: 2*o
O(p^20)
sage: 2*SR(o)
0

The last line is wrong.

Depends on #10846

Component: symbolics

Keywords: sd66

Author: Ralf Stephan

Branch/Commit: 3efac92

Reviewer: Daniel Krenn

Issue created by migration from https://trac.sagemath.org/ticket/18094

[videlec]

comment:1

Surely the big Oh is badly integrated into SR

sage: P.<p> = ZZ[[]]
sage: a = 1/(1+p)
sage: o = a - a.truncate()
sage: bool(SR(o) == 0)
True

[nbruin]

comment:2

At the very least related: #10846, #14693, #16203. Likely a fix there will also fix this ticket.

[rwst]

Dependencies: #10846

[rwst]

comment:3

The fix should be on top of #10846.

[rwst]

Branch: u/rws/multiplication_of_powerseries_wrapped_in_sr_wrong

[rwst]

Author: Ralf Stephan

[rwst]

New commits:

99916f9	10846: fix conversion of power series to symbolic series
26df71b	10846: handle order term correctly
1f25c61	Merge branch 'u/rws/conversion_of_powerseries____sr_bug' of trac.sagemath.org:sage into t/18094/multiplication_of_powerseries_wrapped_in_sr_wrong
48011a4	18094: constants were not handled by 10846: better take the variable from the power series element

[rwst]

Commit: 48011a4

[dkrenn]

comment:6

The example in the ticket now gives:

sage: P.<p> = ZZ[[]]
sage: a = 1/(1+p)
sage: o = a - a.truncate()
sage: 2*SR(o)
2*(Order(p^20))

But it should be Order(p^20).

[dkrenn]

Reviewer: Daniel Krenn