1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
|
(************************************************************************)
(* * The Coq Proof Assistant / The Coq Development Team *)
(* v * Copyright INRIA, CNRS and contributors *)
(* <O___,, * (see version control and CREDITS file for authors & dates) *)
(* \VV/ **************************************************************)
(* // * This file is distributed under the terms of the *)
(* * GNU Lesser General Public License Version 2.1 *)
(* * (see LICENSE file for the text of the license) *)
(************************************************************************)
open NumCompat
open Q.Notations
(** Intervals (extracted from mfourier.ml) *)
(** The type of intervals is *)
type interval = Q.t option * Q.t option
(** None models the absence of bound i.e. infinity
As a result,
- None , None -> \]-oo,+oo\[
- None , Some v -> \]-oo,v\]
- Some v, None -> \[v,+oo\[
- Some v, Some v' -> \[v,v'\]
Intervals needs to be explicitly normalised.
*)
let pp o (n1, n2) =
( match n1 with
| None -> output_string o "]-oo"
| Some n -> Printf.fprintf o "[%s" (Q.to_string n) );
output_string o ",";
match n2 with
| None -> output_string o "+oo["
| Some n -> Printf.fprintf o "%s]" (Q.to_string n)
(** if then interval [itv] is empty, [norm_itv itv] returns [None]
otherwise, it returns [Some itv] *)
let norm_itv itv =
match itv with
| Some a, Some b -> if a <=/ b then Some itv else None
| _ -> Some itv
(** [inter i1 i2 = None] if the intersection of intervals is empty
[inter i1 i2 = Some i] if [i] is the intersection of the intervals [i1] and [i2] *)
let inter i1 i2 =
let l1, r1 = i1 and l2, r2 = i2 in
let inter f o1 o2 =
match (o1, o2) with
| None, None -> None
| Some _, None -> o1
| None, Some _ -> o2
| Some n1, Some n2 -> Some (f n1 n2)
in
norm_itv (inter Q.max l1 l2, inter Q.min r1 r2)
let range = function
| None, _ | _, None -> None
| Some i, Some j -> Some (Q.floor j -/ Q.ceiling i +/ Q.one)
let smaller_itv i1 i2 =
match (range i1, range i2) with
| None, _ -> false
| _, None -> true
| Some i, Some j -> i <=/ j
(** [in_bound bnd v] checks whether [v] is within the bounds [bnd] *)
let in_bound bnd v =
let l, r = bnd in
match (l, r) with
| None, None -> true
| None, Some a -> v <=/ a
| Some a, None -> a <=/ v
| Some a, Some b -> a <=/ v && v <=/ b
|