05_graphs_as_matrices_1.ipynb

05_graphs_as_matrices_2.ipynb

05_graphs_as_matrices_3.ipynb

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   "source": [
    "#The goal of the exercise is to show that (Laplacian = Degree matrix - Adjacency matrix)\n",
    "import networkx as nx \n",
    "import numpy as np"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {
    "collapsed": true
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   "outputs": [],
   "source": [
    "#Read the input data\n",
    "g = nx.read_edgelist(\"data/protein.txt\", delimiter='\\t')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 35,
   "metadata": {},
   "outputs": [
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     "text": [
      "True\n"
     ]
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   ],
   "source": [
    "#Get the adjacency matrix\n",
    "\n",
    "A = nx.to_numpy_matrix(g)\n",
    "\n",
    "D = np.diagflat(A.sum(axis=1))\n",
    "\n",
    "L = nx.laplacian_matrix(g).todense()\n",
    "\n",
    "print(np.all(L==(D-A)))"
   ]
  }
 ],
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