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    "# Operators\n",
    "\n",
    "Operators are important constructs for many quantum applications.  This section covers how to define and use spin operators as well as additional tools for defining more sophisticated operators."
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    "### Constructing Spin Operators\n",
    "\n",
    "The `spin_op`  type provides an abstraction for a general tensor product of Pauli spin operators, and their sums.\n",
    "\n",
    "Spin operators are constructed using the `spin.z()`, `spin.y()`, `spin.x()`, and `spin.i()` functions, corresponding to the $Z$, $Y$, $X$, and $I$ Pauli operators. For example,  `spin.z(0)` corresponds to a Pauli $Z$ operation acting on qubit 0.  The example below demonstrates how to construct the following operator $2XYX - 3ZZY$."
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   "source": [
    "import cudaq\n",
    "from cudaq import spin\n",
    "\n",
    "operator = 2 * spin.x(0) * spin.y(1) * spin.x(2) - 3 * spin.z(0) * spin.z( 1) * spin.y(2)"
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    "There are a number of convenient methods for combining, comparing, iterating through, and extracting information from spin operators and can be referenced [here](https://nvidia.github.io/cuda-quantum/latest/api/languages/python_api.html#cudaq.SpinOperator) in the API."
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    "### Pauli Words and Exponentiating Pauli Words\n",
    "\n",
    "The `pauli_word` type specifies a string of Pauli operations (e.g. ‘XYXZ’) and is convenient for applying operations based on exponentiated Pauli words.  The code below demonstrates how a list of Pauli words, along with their coefficients, are provided as kernel inputs and converted into operators by the `exp_pauli` function.\n",
    "\n",
    "The cell below applies the following operation: $e^{i(0.324IXX)}.e^{i(0.432XYZ)}$"
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    "words = ['XYZ', 'IXX']\n",
    "coefficients = [0.432, 0.324]\n",
    "\n",
    "\n",
    "@cudaq.kernel\n",
    "def kernel(coefficients: list[float], words: list[cudaq.pauli_word]):\n",
    "    q = cudaq.qvector(3)\n",
    "\n",
    "    for i in range(len(coefficients)):\n",
    "        exp_pauli(coefficients[i], q, words[i])"
   ]
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