diff --git a/test/test-ml-data.js b/test/test-ml-data.js
new file mode 100644
index 0000000..e50c6df
--- /dev/null
+++ b/test/test-ml-data.js
@@ -0,0 +1,34 @@
+var data1 = [
+  [0,0,0],
+  [0,1,1],
+  [1,0,1],
+  [1,1,0] 
+]
+
+print(ml.preprocess(data1,'io',{target:2}))
+
+var data2 = {
+  x: [
+    [0,0],
+    [0,1],
+    [1,0],
+    [1,1]
+  ],
+  y: [
+    0,
+    1,
+    1,
+    0
+  ]
+}
+
+print(ml.preprocess(data2,'io',{}))
+
+var data3 = [
+  { a:0, b:0, y: 0 },
+  { a:0, b:1, y: 1 },
+  { a:1, b:0, y: 1 },
+  { a:1, b:1, y: 0 },
+]
+
+print(ml.preprocess(data3,'io',{features:['a','b'],target:'y'}))