Desktop/PPP/python/audio/HammingCode.ipynb

HammingCode74.ipynb

{
  "cells": [
    {
      "metadata": {
        "trusted": true
      },
      "cell_type": "code",
      "source": "class PyHammingCode74:\n    # ハミング符号生成行列\n    _GEN_MAT = np.array([\n        [1,1,0,1],\n        [1,0,1,1],\n        [1,0,0,0],\n        [0,1,1,1],\n        [0,1,0,0],\n        [0,0,1,0],\n        [0,0,0,1]\n    ])\n    # パリティ検査行列\n    _CHECK_MAT = np.array([\n        [1,0,1,0,1,0,1],\n        [0,1,1,0,0,1,1],\n        [0,0,0,1,1,1,1]\n    ])\n    # 復号データ抽出行列\n    _EXTRACT_MAT = np.array([\n        [0,0,1,0,0,0,0],\n        [0,0,0,0,1,0,0],\n        [0,0,0,0,0,1,0],\n        [0,0,0,0,0,0,1],\n    ])\n    # シンドロームから誤りビットの位置を計算する行列\n    _SYNDROME_TO_INDEX_MAT = np.array([1,2,4])\n        \n    def calc_parity(self, data):\n        return np.dot(self._GEN_MAT, data) % 2\n        \n    def correct(self, data):\n        _d = np.copy(data)\n        s = np.dot(self._CHECK_MAT, _d) % 2\n        if np.any(s):\n            i = np.dot(self._SYNDROME_TO_INDEX_MAT, s.T) - 1 # -1で0から始まるインデックスにする\n            _d[i] = _d[i] ^ 1# 誤り符号の訂正\n        return np.dot(self._EXTRACT_MAT, _d)\n",
      "execution_count": 178,
      "outputs": [
        {
          "output_type": "stream",
          "text": "[0 1 0 0 1 0 1]\n[0 1 0 1]\n",
          "name": "stdout"
        }
      ]
    },
    {
      "metadata": {
        "trusted": true
      },
      "cell_type": "code",
      "source": "# データの初期化\ndata = np.array([0,1,0,1])\nprint(\"送信データ: {}\".format(data))\n\n# ハミング符号の計算\nh = PyHammingCode74()\nprint(\"ハミング符号: {}\".format(h.calc_parity(data)))\n\n# ハミング符号の復号\ndata = np.array([0,1,0,0,1,0,1])\nprint(\"受信データ:{}\".format(h.correct(data)))\n\n# 1bit誤りのあるデータの復号\ndata = np.array([1,1,0,0,1,0,1])\nprint(\"受信データ:{}\".format(h.correct(data)))",
      "execution_count": 181,
      "outputs": [
        {
          "output_type": "stream",
          "text": "送信データ: [0 1 0 1]\nハミング符号: [0 1 0 0 1 0 1]\n受信データ:[0 1 0 1]\n受信データ:[0 1 0 1]\n",
          "name": "stdout"
        }
      ]
    }
  ],
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      "language": "python"
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      "file_extension": ".py"
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    "gist": {
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      "data": {
        "description": "Desktop/PPP/python/audio/HammingCode.ipynb",
        "public": true
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