vectorized-finding-a-list-of-strings-in-another-list-of-strings.ipynb

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   "source": [
    "# How to find a list of strings in another list of strings without using for-loops (vectorized)\n",
    "# Via NumPy vectorization"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 66,
   "metadata": {},
   "outputs": [],
   "source": [
    "import numpy as np"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 67,
   "metadata": {},
   "outputs": [],
   "source": [
    "keys = np.array([\"the\", \"hi\", \"a\"])\n",
    "data = np.array([\"hello\", \"a\", \"world\", \"the\", \"python\", \"hi\", \"a\", \"sea\", \"the\"])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 68,
   "metadata": {},
   "outputs": [],
   "source": [
    "indices_matrix = np.char.find(data, keys.reshape(-1,1) )\n",
    "indices = np.where(indices_matrix==0)[1]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 69,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[3 8 5 1 6]\n"
     ]
    }
   ],
   "source": [
    "print(indices)"
   ]
  }
 ],
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