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2019-11-29Return of PR #226: adds relevant theorems when fcycle f (orbit f x) and the ↵Cyril Cohen
needed lemmas (#261) * adds relevant theorems when fcycle f (orbit f x) and the needed lemmas * Generalize f_step lemmas * Generalizations, shorter proofs, bugfixes, CHANGELOG - changelog, renamings and comments - renaming `homo_cycle` to `mem_fcycle` and other small renamings - name swap `mem_orbit` and `in_orbit` - simplifications - generalization following @pi8027's comment - Getting rid of many uniquness condition in `fingraph.v` - added cases to the equivalence `orbitPcycle` - added `cycle_catC`
2019-11-22New generalised induction idiom (#434)Georges Gonthier
Replaced the legacy generalised induction idiom with a more robust one that does not rely on the `{-2}` numerical occurrence selector, using either new helper lemmas `ubnP` and `ltnSE` or a specific `nat` induction principle `ltn_ind`. Added (non-strict in)equality induction helper lemmas Added `ubnP[lg]?eq` helper lemmas that abstract an integer expression along with some (in)equality, in preparation for some generalised induction. Note that while `ubnPleq` is very similar to `ubnP` (indeed `ubnP M` is basically `ubnPleq M.+1`), `ubnPgeq` is used to remember that the inductive value remains below the initial one. Used the change log to give notice to users to update the generalised induction idioms in their proofs to one of the new forms before Mathcomp 1.11.
2019-10-30Change the order of arguments in `ltngtP`Kazuhiko Sakaguchi
from `ltngtP m n : compare_nat m n (m <= n) (n <= m) (m < n) (n < m) (n == m) (m == n)` to `ltngtP m n : compare_nat m n (n == m) (m == n) (n <= m) (m <= n) (n < m) (m < n)`, to make it tries to match subterms with `m < n` first, `m <= n`, then `m == n`.
2019-10-25Stability proofs of sort (#358)Kazuhiko Sakaguchi
* Modified the definition of sort to work on any type * Other Generalizations, fixes and CHANGELOG entry * Add stability lemmas for `path.sort` - Inverse the comparison in `merge` and swap arguments of it everywhere. - Add `sort_rec1` and `sortE` to simplify inductive proofs on `sort`. - Add `seq.mask_filter`, `mem2E`, `path_mask`, `path_filter`, and `sorted_mask`. - Generalize `sorted_filter`, `homo_path_in`, `mono_path_in`, `homo_sorted_in`, and `mono_sorted_in` to non-`eqType`s. - Add the following lemmas to state the stability of `path.merge` and `path.sort`. sorted_merge : forall (T : Type) (leT : rel T), transitive leT -> forall s t : seq T, sorted leT (s ++ t) -> merge leT s t = s ++ t merge_stable_path : forall (T : Type) (leT leT' : rel T), total leT -> forall (x : T) (s1 s2 : seq T), all (fun y : T => all (leT' y) s2) s1 -> path [rel x0 y | leT x0 y && (leT y x0 ==> leT' x0 y)] x s1 -> path [rel x0 y | leT x0 y && (leT y x0 ==> leT' x0 y)] x s2 -> path [rel x0 y | leT x0 y && (leT y x0 ==> leT' x0 y)] x (merge leT s1 s2) merge_stable_sorted : forall (T : Type) (leT leT' : rel T), total leT -> forall s1 s2 : seq T, all (fun x : T => all (leT' x) s2) s1 -> sorted [rel x y | leT x y && (leT y x ==> leT' x y)] s1 -> sorted [rel x y | leT x y && (leT y x ==> leT' x y)] s2 -> sorted [rel x y | leT x y && (leT y x ==> leT' x y)] (merge leT s1 s2) sorted_sort : forall (T : Type) (leT : rel T), transitive leT -> forall s : seq T, sorted leT s -> sort leT s = s sort_stable : forall (T : Type) (leT leT' : rel T), total leT -> transitive leT' -> forall s : seq T, sorted leT' s -> sorted [rel x y | leT x y && (leT y x ==> leT' x y)] (sort leT s) filter_sort : forall (T : Type) (leT : rel T), total leT -> transitive leT -> forall (p : pred T) (s : seq T), [seq x <- sort leT s | p x] = sort leT [seq x <- s | p x] mask_sort : forall (T : Type) (leT : rel T), total leT -> transitive leT -> forall (s : seq T) (m : bitseq), {m_s : bitseq | mask m_s (sort leT s) = sort leT (mask m s)} mask_sort' : forall (T : Type) (leT : rel T), total leT -> transitive leT -> forall (s : seq T) (m : bitseq), sorted leT (mask m s) -> {m_s : bitseq | mask m_s (sort leT s) = mask m s} subseq_sort : forall (T : eqType) (leT : rel T), total leT -> transitive leT -> {homo sort leT : t s / subseq t s} subseq_sort' : forall (T : eqType) (leT : rel T), total leT -> transitive leT -> forall t s : seq T, subseq t s -> sorted leT t -> subseq t (sort leT s) mem2_sort : forall (T : eqType) (leT : rel T), total leT -> transitive leT -> forall (s : seq T) (x y : T), leT x y -> mem2 s x y -> mem2 (sort leT s) x y * Avoid some eta-expansions * Get the proper fix of `order_path_min` and remove `sort_map_in` * Update documentation and CHANGELOG entries
2019-05-17refactor `seq` permutation theoryGeorges Gonthier
- Change the naming of permutation lemmas so they conform to a consistent policy: `perm_eq` lemmas have a `perm_` (_not_ `perm_eq`) prefix, or sometimes a `_perm` suffix for lemmas that _prove_ `perm_eq` using a property when there is also a lemma _using_ `perm_eq` for the same property. Lemmas that do not concern `perm_eq` do _not_ have `perm` in their name. - Change the definition of `permutations` for a time- and space- back-to-front generation algorithm. - Add frequency tally operations `tally`, `incr_tally`, `wf_tally` and `tally_seq`, used by the improved `permutation` algorithm. - add deprecated aliases for renamed lemmas
2019-04-26Cleaning Require and Require ImportsCyril Cohen
2018-12-19Generalizing homo-mono-morphism lemmas and extremum (#201)Cyril Cohen
2018-11-21Merge Arguments and Prenex ImplicitsAnton Trunov
See the discussion here: https://github.com/math-comp/math-comp/pull/242#discussion_r233778114
2018-07-12Replace all the CoInductives with VariantsKazuhiko Sakaguchi
2018-02-21Change Implicit Arguments to Arguments in ssreflectJasper Hugunin
2018-02-06fixing things that @ggonthier and @ybertot spotted and some I spottedCyril Cohen
2018-02-06running semi-automated linting on the whole libraryCyril Cohen
2016-11-07update copyright bannerAssia Mahboubi
2015-11-05merge basic/ into ssreflect/Enrico Tassi