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        "---\n",
        "title: \"Medir qubits\"\n",
        "description: \"Aprenda a medir qubits, incluidas las restricciones sobre dónde se pueden utilizar las mediciones.\"\n",
        "---\n",
        "\n",
        "<span id=\"measure-qubits\" />\n",
        "\n",
        "# Medir qubits\n",
        "\n"
      ]
    },
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        "{/*\n",
        "  DO NOT EDIT THIS CELL!!!\n",
        "  This cell's content is generated automatically by a script. Anything you add\n",
        "  here will be removed next time the notebook is run. To add new content, create\n",
        "  a new cell before or after this one.\n",
        "  */}\n",
        "\n",
        "<Accordion>\n",
        "  <AccordionItem title=\"Versiones del paquete\">\n",
        "    El código de esta página se ha desarrollado teniendo en cuenta los siguientes requisitos.\n",
        "    Recomendamos utilizar estas versiones o versiones más recientes.\n",
        "\n",
        "    ```\n",
        "    qiskit[all]~=2.5.0\n",
        "    ```\n",
        "  </AccordionItem>\n",
        "</Accordion>\n",
        "\n"
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        "Para obtener información sobre el estado de un qubit, se puede *medir* en un [bit clásico](/docs/api/qiskit/circuit#qiskit.circuit.Clbit). En Qiskit, las mediciones se realizan en la base computacional, es decir, la base Pauli- $Z$ de un solo qubit. Por lo tanto, una medición da 0 o 1, dependiendo del solapamiento con los estados propios de Pauli- $Z$ $|0\\rangle$ y $|1\\rangle$ :\n",
        "\n",
        "$$\n",
        "|q\\rangle \\xrightarrow{measure}\\begin{cases}\n",
        "      0 (\\text{outcome}+1), \\text{with probability } p_0=|\\langle q|0\\rangle|^{2}\\text{,} \\\\\n",
        "      1 (\\text{outcome}-1), \\text{with probability } p_1=|\\langle q|1\\rangle|^{2}\\text{.}\n",
        "    \\end{cases}\n",
        "$$\n",
        "\n",
        "<span id=\"apply-a-measurement-to-a-circuit\" />\n",
        "\n",
        "## Aplicar una medida a un circuito\n",
        "\n",
        "Hay varias formas de aplicar medidas a un circuito:\n",
        "\n",
        "<span id=\"quantumcircuitmeasure-method\" />\n",
        "\n",
        "### Método de `QuantumCircuit.measure`\n",
        "\n",
        "Utilice el [`measure`](/docs/api/qiskit/qiskit.circuit.QuantumCircuit#measure) método para medir un [`QuantumCircuit`](/docs/api/qiskit/qiskit.circuit.QuantumCircuit#quantumcircuit-class).\n",
        "\n",
        "Ejemplos:\n",
        "\n"
      ]
    },
    {
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        }
      ],
      "source": [
        "from qiskit import QuantumCircuit\n",
        "\n",
        "qc = QuantumCircuit(5, 5)\n",
        "qc.x(0)\n",
        "qc.x(1)\n",
        "qc.x(4)\n",
        "qc.measure(\n",
        "    range(5), range(5)\n",
        ")  #  Measures all qubits into the corresponding clbit."
      ]
    },
    {
      "cell_type": "code",
      "execution_count": 2,
      "id": "5c629673-9000-47ae-8bd3-f3fef65f8b0c",
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          },
          "execution_count": 2,
          "metadata": {},
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      ],
      "source": [
        "from qiskit import QuantumCircuit\n",
        "\n",
        "qc = QuantumCircuit(3, 1)\n",
        "qc.x([0, 2])\n",
        "qc.measure(1, 0)  # Measure qubit 1 into the classical bit 0."
      ]
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      "source": [
        "<span id=\"measure-class\" />\n",
        "\n",
        "### `Measure` clase\n",
        "\n",
        "La clase Qiskit [Measure](/docs/api/qiskit/circuit#qiskit.circuit.Measure) mide los qubits especificados.\n",
        "\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": 3,
      "id": "b8855eed-8238-41ce-a45d-f8e81da05508",
      "metadata": {},
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        {
          "data": {
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          },
          "execution_count": 3,
          "metadata": {},
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        }
      ],
      "source": [
        "from qiskit.circuit import Measure\n",
        "\n",
        "qc = QuantumCircuit(3, 1)\n",
        "qc.x([0, 1])\n",
        "qc.append(Measure(), [0], [0])  # measure qubit 0 into clbit 0"
      ]
    },
    {
      "cell_type": "markdown",
      "id": "6583286c-d8e3-4adf-8bce-0e7d9dc3c44f",
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      "source": [
        "<span id=\"quantumcircuitmeasure_all-method\" />\n",
        "\n",
        "### Método de `QuantumCircuit.measure_all`\n",
        "\n",
        "Para medir todos los qubits en los bits clásicos correspondientes, utilice el método [`measure_all`](/docs/api/qiskit/qiskit.circuit.QuantumCircuit#measure_all) método. Por defecto, este método añade nuevos bits clásicos en un `ClassicalRegister` para almacenar estas mediciones.\n",
        "\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": 4,
      "id": "cac45158-7e3e-47b6-bc89-8ac3a4bc9539",
      "metadata": {},
      "outputs": [],
      "source": [
        "from qiskit import QuantumCircuit\n",
        "\n",
        "qc = QuantumCircuit(3, 1)\n",
        "qc.x([0, 2])\n",
        "qc.measure_all()  # Measure all qubits."
      ]
    },
    {
      "cell_type": "markdown",
      "id": "8b4a57d5-ffc9-4247-b39c-2e19ab2c185b",
      "metadata": {},
      "source": [
        "<span id=\"quantumcircuitmeasure_active-method\" />\n",
        "\n",
        "### Método de `QuantumCircuit.measure_active`\n",
        "\n",
        "Para medir todos los qubits que no están inactivos, utilice el método [`measure_active`](/docs/api/qiskit/qiskit.circuit.QuantumCircuit#measure_active) método. Este método crea un nuevo `ClassicalRegister` con un tamaño igual al número de qubits no ociosos que se están midiendo.\n",
        "\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": 5,
      "id": "3161f70d-5c59-48fa-842f-624ce7ed0bbe",
      "metadata": {},
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      "source": [
        "from qiskit import QuantumCircuit\n",
        "\n",
        "qc = QuantumCircuit(3, 1)\n",
        "qc.x([0, 2])\n",
        "qc.measure_active()  # Measure qubits that are not idle, that is, qubits 0 and 2."
      ]
    },
    {
      "cell_type": "markdown",
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      "source": [
        "<span id=\"next-steps\" />\n",
        "\n",
        "## Próximos pasos\n",
        "\n",
        "<Admonition type=\"tip\" title=\"Recomendaciones\">\n",
        "  * [`Measure`](/docs/api/qiskit/circuit#qiskit.circuit.Measure) clase\n",
        "  * [`measure_all`](/docs/api/qiskit/qiskit.circuit.QuantumCircuit#measure_all) método\n",
        "  * [`measure_active`](/docs/api/qiskit/qiskit.circuit.QuantumCircuit#measure_active) método\n",
        "  * [`random_circuit`](/docs/api/qiskit/circuit_random#qiskit.circuit.random.random_circuit) método\n",
        "  * [Mediciones en medio del circuito](/docs/guides/execute-dynamic-circuits#midcircuit) (Disponibles únicamente cuando se utiliza « Qiskit Runtime »)\n",
        "</Admonition>\n",
        "\n"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "id": "a1b8767d",
      "source": "© IBM Corp., 2017-2026"
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