From 0018c91fb6846df6392678753b6ca47a07c7ec3b Mon Sep 17 00:00:00 2001
From: Sergiu Ivanov <sivanov@colimite.fr>
Date: Mon, 9 May 2022 10:54:53 +0200
Subject: [PATCH] Type list-syntactic-interactions.

---
 networks.rkt               | 46 ++++++++++++++------------------------
 scribblings/networks.scrbl | 21 +++++++++++++++++
 2 files changed, 38 insertions(+), 29 deletions(-)

diff --git a/networks.rkt b/networks.rkt
index df093ac..1b8da94 100644
--- a/networks.rkt
+++ b/networks.rkt
@@ -22,6 +22,8 @@
    network-form->network/any network-form->network/boolean
    network-form->network/01 make-boolean-network-form
    forms->boolean-network
+
+   list-syntactic-interactions
    )
 
   (define-type (State a) (VariableMapping a))
@@ -238,6 +240,20 @@
                                               'b '(not b))))
       (check-equal? (network-domains n) (hash 'a '(#f #t)
                                               'b '(#f #t)))))
+
+  (: list-syntactic-interactions
+     (All (a) (-> (NetworkForm a) Variable (Listof Variable))))
+  (define (list-syntactic-interactions nf x)
+    (set-intersect
+     (extract-symbols (hash-ref (network-form-forms nf) x))
+     (hash-keys (network-form-forms nf))))
+
+  (module+ test
+    (test-case "list-syntactic-interactions"
+      (define n (make-boolean-network-form #hash((a . (+ a b c))
+                                                 (b . (- b c)))))
+      (check-true (set=? (list-syntactic-interactions n 'a) '(a b)))
+      (check-true (set=? (list-syntactic-interactions n 'b) '(b)))))
   )
 
 (require 'typed)
@@ -254,8 +270,7 @@
                [struct dynamics ([network network?]
                                  [mode mode?])])
  ;; Functions
- (contract-out [list-syntactic-interactions (-> network-form? variable? (listof variable?))]
-               [build-syntactic-interaction-graph (-> network-form? graph?)]
+ (contract-out [build-syntactic-interaction-graph (-> network-form? graph?)]
                [interaction? (-> network? variable? variable? boolean?)]
                [get-interaction-sign (-> network? variable? variable? (or/c #f -1 0 1))]
                [build-interaction-graph (-> network? graph?)]
@@ -405,34 +420,7 @@
 ;;; Inferring interaction graphs
 ;;; ============================
 
-;;; In this section I provide inference of both unsigned and signed
-;;; interaction graphs, but since the inference of signed interaction
-;;; graphs is based on analysing the dynamics of the networks, it may
-;;; be quite resource-consuming, especially since I allow any
-;;; syntactic forms in the definitions of the functions.
-;;;
-;;; Note the fine difference between syntactic interaction graphs and
-;;; interaction graphs generated from the dynamics of the network.
-;;; The syntactic interaction graphs are based on the whether
-;;; a variable appears or not in the form of the function for another
-;;; variable.  On the other hand, the normal, conventional interaction
-;;; graph records the fact that one variable has an impact on the
-;;; dynamics of the other variable.  Depending on the model, these may
-;;; or may not be the same.
 
-;;; Lists the variables of the network form appearing in the update
-;;; function form for x.
-(define (list-syntactic-interactions nf x)
-  (set-intersect
-   (extract-symbols (hash-ref (network-form-forms nf) x))
-   (hash-keys (network-form-forms nf))))
-
-(module+ test
-  (test-case "list-syntactic-interactions"
-    (define n (make-boolean-network-form #hash((a . (+ a b c))
-                                               (b . (- b c)))))
-    (check-true (set=? (list-syntactic-interactions n 'a) '(a b)))
-    (check-true (set=? (list-syntactic-interactions n 'b) '(b)))))
 
 ;;; Builds the graph in which the vertices are the variables of a
 ;;; given network, and which contains an arrow from a to b whenever a
diff --git a/scribblings/networks.scrbl b/scribblings/networks.scrbl
index 1a73157..b99b5a6 100644
--- a/scribblings/networks.scrbl
+++ b/scribblings/networks.scrbl
@@ -346,6 +346,27 @@ a change in the value of @tt{y}.  Thus the syntactic interaction graph may have
 extra arcs if @tt{x} appears in the form of @tt{y}, but has no actual influence
 on @tt{y}.
 
+@defproc[(list-syntactic-interactions [nf (NetworkForm a)]
+				      [x Variable])
+				      (Listof Variable)]{
+
+Lists the variables of the network form appearing in the update function form
+for @racket[x].
+
+The variables which are not part of the network are excluded from the listing.
+
+@ex[
+(list-syntactic-interactions
+ (make-boolean-network-form #hash((a . (+ a b))
+                                  (b . (- b))))
+ 'a)
+(list-syntactic-interactions
+ (make-boolean-network-form #hash((a . (+ a b c))
+                                  (b . (- b c))))
+ 'a)
+]}
+
+
 @section{Dynamics of networks}
 
 This section contains definitions for building and analysing the dynamics