specify minimum value of node with node.minValue

README.md

@@ -61,7 +61,7 @@ Each *node* must be an object. The following properties are assigned by the [San
 
 * *node*.sourceLinks - the array of outgoing [links](#sankey_links) which have this node as their source
 * *node*.targetLinks - the array of incoming [links](#sankey_links) which have this node as their target
-* *node*.value - the node’s value; if not defined, this is the sum of *link*.value for the node’s incoming [links](#sankey_links)
+* *node*.value - the node’s value; this is the sum of *link*.value for the node’s incoming [links](#sankey_links) (or *node*.minValue if defined and is greater)
 * *node*.index - the node’s zero-based index within the array of nodes
 * *node*.depth - the node’s zero-based graph depth, derived from the graph topology
 * *node*.height - the node’s zero-based graph height, derived from the graph topology

src/sankey.js

@@ -135,7 +135,7 @@ export default function() {
       node.value = Math.max(
         sum(node.sourceLinks, value),
         sum(node.targetLinks, value),
-        typeof node.value !== 'undefined' ? node.value : 0
+        typeof node.minValue !== 'undefined' ? node.minValue : 0
       );
     });
   }