Lazy OEIS sequences - Githubissues

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Lazy OEIS sequences #28627

Closed edd8e884-f507-429a-b577-5d554626c0fe closed 4 years ago

edd8e884-f507-429a-b577-5d554626c0fe commented 5 years ago

We make the OEISSequences be (uniquely) defined as long as their ID (A-number) is known, and connect to the internet as late as possible.

CC: @fchapoton @mo271 @videlec @seblabbe

Component: combinatorics

Author: Thierry Monteil

Branch/Commit: ecd06dd

Reviewer: Sébastien Labbé

Issue created by migration from https://trac.sagemath.org/ticket/28627

edd8e884-f507-429a-b577-5d554626c0fe commented 5 years ago

Branch: u/tmonteil/lazy_oeis_sequences

edd8e884-f507-429a-b577-5d554626c0fe commented 5 years ago

Commit: 446af98

edd8e884-f507-429a-b577-5d554626c0fe commented 5 years ago

New commits:

`13bc675`	`#28627 : lazy creation of OEIS sequences based only on their A-number`
`203f63e`	`#28627 : different imaginary sequences must have different A-numbers`
`0ce1c0b`	`#28627 : dedicated handling of dead sequences`
`afa2833`	`#28627 : replace obsolete warning with a note`
`446af98`	`#28627 : examples are intended for humans`

edd8e884-f507-429a-b577-5d554626c0fe commented 5 years ago

comment:3

I tried to cut the changes into meaningful commits, however the block

+        TESTS::
+
+        sage: s = oeis._imaginary_sequence(ident='A004238')
+        sage: s
+        A004238: The characteristic sequence of 42 plus one, starting from 38.
+        sage: s.online_update()                         # optional -- internet
+        sage: s                                         # optional -- internet
+        A004238: a(n) = 100*log(n) rounded to nearest integer.

should appear in the second commit, not the first, since at this stage ident parameter is not defined for imaginary sequences.

You should test the whole branch, the commits are made to ease human review.

edd8e884-f507-429a-b577-5d554626c0fe commented 5 years ago

comment:4

Patchbot complains about doctest coverage regression.