1.3 numpy的广播与转置.ipynb

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   "source": [
    "import numpy as np"
   ]
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  {
   "cell_type": "markdown",
   "id": "98df98d3",
   "metadata": {},
   "source": [
    "# numpy广播"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "id": "8c37f4d3",
   "metadata": {},
   "outputs": [],
   "source": [
    "a = np.arange(10).reshape(2,5)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "id": "87ae4f33",
   "metadata": {},
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    {
     "data": {
      "text/plain": [
       "array([[0, 1, 2, 3, 4],\n",
       "       [5, 6, 7, 8, 9]])"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
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   "source": [
    "a"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "id": "d395e529",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "array([[10, 11, 12, 13, 14],\n",
       "       [15, 16, 17, 18, 19]])"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
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   "source": [
    "a+10"
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   "execution_count": 5,
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       "array([[  0, 100, 200, 300, 400],\n",
       "       [500, 600, 700, 800, 900]])"
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     "execution_count": 5,
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   "source": [
    "a*100"
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   "execution_count": 6,
   "id": "f9d70024",
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      "text/plain": [
       "array([[ 0,  2,  4,  6,  8],\n",
       "       [10, 12, 14, 16, 18]])"
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     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
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   "source": [
    "a + a"
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   "execution_count": 7,
   "id": "89d0d6d8",
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     "data": {
      "text/plain": [
       "array([[0, 1, 2, 3, 4],\n",
       "       [5, 6, 7, 8, 9]])"
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     "execution_count": 7,
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    "a"
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   "cell_type": "code",
   "execution_count": 8,
   "id": "489bc895",
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   "outputs": [],
   "source": [
    "a1 = np.arange(5)"
   ]
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   "cell_type": "code",
   "execution_count": 12,
   "id": "914e0d52",
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    "a1"
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   "execution_count": 9,
   "id": "e9274753",
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   "outputs": [
    {
     "data": {
      "text/plain": [
       "(5,)"
      ]
     },
     "execution_count": 9,
     "metadata": {},
     "output_type": "execute_result"
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   ],
   "source": [
    "a1.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "id": "5674dbda",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(2, 5)"
      ]
     },
     "execution_count": 10,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "a.shape"
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   "execution_count": 11,
   "id": "ef67401f",
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   "outputs": [
    {
     "data": {
      "text/plain": [
       "array([[ 0,  2,  4,  6,  8],\n",
       "       [ 5,  7,  9, 11, 13]])"
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     "execution_count": 11,
     "metadata": {},
     "output_type": "execute_result"
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   "source": [
    "a + a1"
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   "cell_type": "code",
   "execution_count": 15,
   "id": "d93a06bc",
   "metadata": {},
   "outputs": [],
   "source": [
    "a1 = np.arange(2)"
   ]
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   "cell_type": "code",
   "execution_count": 17,
   "id": "7dc58504",
   "metadata": {},
   "outputs": [
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     "data": {
      "text/plain": [
       "array([[0],\n",
       "       [1]])"
      ]
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     "execution_count": 17,
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     "output_type": "execute_result"
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   ],
   "source": [
    "a1 = a1.reshape(2,1)\n",
    "a1"
   ]
  },
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   "cell_type": "code",
   "execution_count": 18,
   "id": "0cb3c99d",
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    {
     "data": {
      "text/plain": [
       "array([[ 0,  1,  2,  3,  4],\n",
       "       [ 6,  7,  8,  9, 10]])"
      ]
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     "execution_count": 18,
     "metadata": {},
     "output_type": "execute_result"
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   "source": [
    "a + a1"
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  {
   "cell_type": "markdown",
   "id": "81cc0718",
   "metadata": {},
   "source": [
    "# 转置"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "id": "7a7a3734",
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   "outputs": [
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     "data": {
      "text/plain": [
       "(2, 5)"
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     "execution_count": 19,
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    "a.shape"
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       "array([[0, 5],\n",
       "       [1, 6],\n",
       "       [2, 7],\n",
       "       [3, 8],\n",
       "       [4, 9]])"
      ]
     },
     "execution_count": 20,
     "metadata": {},
     "output_type": "execute_result"
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   "source": [
    "a.T "
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   "execution_count": null,
   "id": "8472d826",
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