From cd8cada92e4d9f807787e466b0685951f630b54d Mon Sep 17 00:00:00 2001
From: Sergiu Ivanov <sivanov@colimite.fr>
Date: Thu, 25 May 2023 15:19:25 +0200
Subject: [PATCH] Add sbfs/state->lists+headers.

---
 scribblings/tbn.scrbl | 11 +++++++++++
 tbn.rkt               | 19 ++++++++++++++++++-
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/scribblings/tbn.scrbl b/scribblings/tbn.scrbl
index 464cb88..8d9f341 100644
--- a/scribblings/tbn.scrbl
+++ b/scribblings/tbn.scrbl
@@ -245,6 +245,17 @@ whether it is actually 0:
 (sbfs/state->lists (list (tbf/state (hash 'a 1 'b 2) 3)))
 ]}
 
+@defproc[(sbfs/state->lists+headers [sbfs (Listof TBF/State)])
+				    (Pairof (Listof Variable) (Listof (Listof Real)))]{
+
+Like @racket[sbfs/state->lists], but also shows the names of the
+variables as column headers.
+
+@ex[
+(sbfs/state->lists+headers (list (tbf/state (hash 'a 1 'b 2) 0)
+                      	   	 (tbf/state (hash 'a -2 'b 1) 0)))
+]}
+
 @section{Tabulating TBFs and SBFs}
 
 @defproc[(tabulate-tbfs/state [tbfs (Listof TBF/State)]) (Listof (Listof Real))]{
diff --git a/tbn.rkt b/tbn.rkt
index 3ea212d..ea78049 100644
--- a/tbn.rkt
+++ b/tbn.rkt
@@ -29,7 +29,7 @@
    lists+vars->sbfs/state lists+headers->sbfs/state lists->sbfs/state
    read-org-tbfs/state read-org-tbfs/state+headers
    tbfs/state->lists tbfs/state->lists+headers
-   sbfs/state->lists
+   sbfs/state->lists sbfs/state->lists+headers
 
    tabulate-tbfs/state tabulate-tbfs/state+headers
    tabulate-tbf/state tabulate-tbf/state+headers
@@ -234,6 +234,23 @@
                                 (tbf/state (hash 'a -2 'b 1) 0)))
        '((1 2) (-2 1)))))
 
+  (: sbfs/state->lists+headers (-> (Listof TBF/State)
+                                   (Pairof (Listof Variable)
+                                           (Listof (Listof Real)))))
+  (define (sbfs/state->lists+headers tbfs)
+    (cons (hash-map (tbf/state-w (car tbfs))
+                    (λ ([x : Symbol] _) x) #t)
+          (sbfs/state->lists tbfs)))
+
+  (module+ test
+    (test-case "sbfs/state->list+headers"
+      (check-equal?
+       (sbfs/state->lists+headers (list (tbf/state (hash 'a 1 'b 2) 0)
+                                        (tbf/state (hash 'a -2 'b 1) 0)))
+       '((a b)
+         (1 2)
+         (-2 1)))))
+
   (: tabulate-tbfs/state (-> (Listof TBF/State) (Listof (Listof Real))))
   (define (tabulate-tbfs/state tbfs)
     (define vars (hash-map (tbf/state-w (car tbfs)) (λ ([x : Variable] _) x) #t))