moved nmf and kmeans around

Table_of_Contents.ipynb

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@@ -56,15 +56,43 @@
      "metadata": {},
      "source": [
       "1.  [Segmentation](notebooks/segmentation.ipynb)\n",
+      "1.  [Onset Detection](notebooks/onset_detection.ipynb)"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Feature Extraction"
+     ]
+    },
+    {
+     "cell_type": "markdown",
+     "metadata": {},
+     "source": [
       "1.  [Feature Extraction](notebooks/feature_extraction.ipynb)\n",
       "1.  [Spectral Features](notebooks/spectral_features.ipynb)\n",
       "1.  [Onset Detection](notebooks/onset_detection.ipynb)\n",
+      "1.  [Mel-Frequency Ceptral Coefficients](notebooks/mfcc.ipynb)"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Machine Learning"
+     ]
+    },
+    {
+     "cell_type": "markdown",
+     "metadata": {},
+     "source": [
       "1.  [K-Nearest Neighbor](notebooks/knn.ipynb)\n",
-      "1.  [Mel-Frequency Ceptral Coefficients](notebooks/mfcc.ipynb)\n",
-      "1.  [Cross Validation](notebooks/cross_validation.ipynb)\n",
-      "1.  [Unsupervised Classification]()\n",
+      "1.  [K-Means Clustering](notebooks/kmeans.ipynb)\n",
       "1.  [Nonnegative Matrix Factorization](notebooks/nmf.ipynb)\n",
-      "1.  [Source Separation]()"
+      "1.  [Cross Validation](notebooks/cross_validation.ipynb)"
      ]
     },
     {
@@ -80,7 +108,9 @@
      "metadata": {},
      "source": [
       "1.  [Understanding Audio Features through Sonification](exercises/feature_sonification.ipynb)\n",
-      "1.  [Instrument Classification using K-NN](exercises/knn_instrument_classification.ipynb)"
+      "1.  [Instrument Classification using K-NN](exercises/knn_instrument_classification.ipynb)\n",
+      "1.  [Unsupervised Instrument Classification using K-Means](exercises/)\n",
+      "1.  [Source Separation using NMF](exercises/nmf_source_separation.ipynb)"
      ]
     },
     {

notebooks/lab4.ipynb → exercises/nmf_source_separation.ipynb

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  "worksheets": [
   {
    "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "Exercise: Source Separation using NMF"
+     ]
+    },
     {
      "cell_type": "markdown",
      "metadata": {},

notebooks/lab3.ipynb → notebooks/kmeans.ipynb

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@@ -13,7 +13,7 @@
      "level": 1,
      "metadata": {},
      "source": [
-      "Clustering"
+      "K-Means Clustering"
      ]
     },
     {