diff --git a/lib/labeledgraph.js b/lib/labeledgraph.js
index 01d8322..7e3012a 100644
--- a/lib/labeledgraph.js
+++ b/lib/labeledgraph.js
@@ -21,6 +21,8 @@ function drawGraphInner({nodes, links}){
 
     // List of node ids
     var nodeids = nodes.map(function(d){return d.id})
+    var positionById = {}
+    nodeids.forEach((nodeid, i) => positionById[nodeid]=i)
     
     // A linear scale to position the nodes on the X axis
     var x = d3.scalePoint()
@@ -56,9 +58,9 @@ function drawGraphInner({nodes, links}){
         .enter()
         .append('path')
         .attr('d', function (d) {
-            let start = x(d.source)    
+            let start = x(positionById[d.source])    
                 // X position of start node on the X axis
-            let end = x(d.target)      
+            let end = x(positionById[d.target])      
                 // X position of end node
             return ['M', 
                 start, 
@@ -83,9 +85,9 @@ function drawGraphInner({nodes, links}){
         .enter()
         .append("text")
         .attr("x", function(d){ 
-            let start = x(d.source)    
+            let start = x(positionById[d.source])    
                 // X position of start node on the X axis
-            let end = x(d.target)      
+            let end = x(positionById[d.target])      
                 // X position of end node
             return start + (end-start)/2 -4*getlength(d.distance)
         })