diff --git a/utils-tests.rkt b/utils-tests.rkt
index eec26d4..593ada8 100644
--- a/utils-tests.rkt
+++ b/utils-tests.rkt
@@ -68,7 +68,11 @@
          [dbl (λ (x) (let ([x-str (symbol->string x)])
                        (string->symbol (string-append x-str x-str))))]
          [new-gr1 (update-vertices/unweighted gr1 dbl)]
-         [new-gr2 (update-vertices/unweighted gr2 dbl)])
+         [new-gr2 (update-vertices/unweighted gr2 dbl)]
+         [new-gr1-ug (update-graph gr1 #:v-func dbl)]
+         [new-gr2-ug (update-graph gr2 #:v-func dbl)]
+         [gr3 (weighted-graph/directed '((10 a b) (11 b c)))]
+         [new-gr3 (update-graph gr3 #:v-func dbl #:e-func (λ (x) (* 2 x)))])
     (check-false (has-vertex? new-gr1 'a))
     (check-true (has-vertex? new-gr1 'aa))
     (check-false (has-vertex? new-gr1 'b))
@@ -81,4 +85,25 @@
     (check-true (has-edge? new-gr2 'aa 'bb))
     (check-true (has-edge? new-gr2 'bb 'aa))
     (check-true (has-edge? new-gr2 'bb 'cc))
-    (check-true (has-edge? new-gr2 'cc 'bb))))
+    (check-true (has-edge? new-gr2 'cc 'bb))
+
+    (check-false (has-vertex? new-gr1-ug 'a))
+    (check-true (has-vertex? new-gr1-ug 'aa))
+    (check-false (has-vertex? new-gr1-ug 'b))
+    (check-true (has-vertex? new-gr1-ug 'bb))
+    (check-false (has-vertex? new-gr1-ug 'c))
+    (check-true (has-vertex? new-gr1-ug 'cc))
+    (check-true (has-edge? new-gr1-ug 'aa 'bb))
+    (check-true (has-edge? new-gr1-ug 'bb 'cc))
+
+    (check-true (has-edge? new-gr2-ug 'aa 'bb))
+    (check-true (has-edge? new-gr2-ug 'bb 'aa))
+    (check-true (has-edge? new-gr2-ug 'bb 'cc))
+    (check-true (has-edge? new-gr2-ug 'cc 'bb))
+
+    (check-true (has-edge? new-gr3 'aa 'bb))
+    (check-false (has-edge? new-gr3 'bb 'aa))
+    (check-true (has-edge? new-gr3 'bb 'cc))
+    (check-false (has-edge? new-gr3 'cc 'bb))
+    (check-equal? (edge-weight new-gr3 'aa 'bb) 20)
+    (check-equal? (edge-weight new-gr3 'bb 'cc) 22)))
diff --git a/utils.rkt b/utils.rkt
index 003a454..90ea98b 100644
--- a/utils.rkt
+++ b/utils.rkt
@@ -19,7 +19,11 @@
                [unstringify-pairs (-> (listof (general-pair/c string? any/c))
                                       (listof (general-pair/c symbol? any/c)))]
                [read-org-variable-mapping (-> string? variable-mapping?)]
-               [update-vertices/unweighted (-> graph? (-> any/c any/c) graph?)])
+               [update-vertices/unweighted (-> graph? (-> any/c any/c) graph?)]
+               [update-graph (->* (graph?)
+                                  (#:v-func (-> any/c any/c)
+                                   #:e-func (-> any/c any/c))
+                                  graph?)])
  ;; Contracts
  (contract-out [variable-mapping? contract?]
                [string-variable-mapping? contract?]
@@ -228,3 +232,20 @@
    (for/list ([e (in-edges gr)])
      (match-let ([(list u v) e])
        (list (func u) (func v))))))
+
+;;; Given a graph, apply a transformation v-func to every vertex label
+;;; and, if the graph is a weighted graph, the transformation e-func
+;;; to every edge label.  Both transformations default to identity
+;;; functions.  If gr is an weighted graph, the result is a weighted
+;;; graph.  If gr is an unweighted graph, the result is an unweighted
+;;; graph.
+(define (update-graph gr #:v-func [v-func identity] #:e-func [e-func identity])
+  (let ([edges (for/list ([e (in-edges gr)])
+                 (match-let ([(list u v) e])
+                   (if (unweighted-graph? gr)
+                       (list (v-func u) (v-func v))
+                       (list (e-func (edge-weight gr u v))
+                             (v-func u) (v-func v)))))])
+    (if (unweighted-graph? gr)
+        (unweighted-graph/directed edges)
+        (weighted-graph/directed edges))))