diff --git a/Classes/BuboArray.sc b/Classes/BuboArray.sc
index b947bef..5cf7ecd 100644
--- a/Classes/BuboArray.sc
+++ b/Classes/BuboArray.sc
@@ -101,7 +101,7 @@
   }
 
   pwrand { arg weights, repeats=1;
-    ^Pwrand(this, weights, repeats);
+    ^Pwrand(this, weights.normalizeSum, repeats);
   }
 
   pwhite { arg repeats=inf;
diff --git a/Classes/PDyn.sc b/Classes/PDyn.sc
new file mode 100644
index 0000000..be92a54
--- /dev/null
+++ b/Classes/PDyn.sc
@@ -0,0 +1,10 @@
+Pdyn {
+  *new {
+    arg function, hash;
+    if (hash.isNil) { hash = 10.collect({
+      "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ".choose })
+      .join("").asSymbol;
+    }
+    ^Pfunc({Ndef(hash, function).asMap})
+  }
+}