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class QasmQobj(qobj_id=None, config=None, experiments=None, header=None)

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Bases: object

A QASM Qobj.

Instantiate a new QASM Qobj Object.

Each QASM Qobj object is used to represent a single payload that will be passed to a Qiskit provider. It mirrors the Qobj the published Qobj specification(opens in a new tab) for OpenQASM experiments.


  • qobj_id (str) – An identifier for the qobj
  • config (QasmQobjRunConfig) – A config for the entire run
  • header (QobjHeader) – A header for the entire run
  • experiments (list) – A list of lists of QasmQobjExperiment objects representing an experiment



classmethod QasmQobj.from_dict(data)

Create a new QASMQobj object from a dictionary.


data (dict) – A dictionary representing the QasmQobj to create. It will be in the same format as output by to_dict().


The QasmQobj from the input dictionary.

Return type




Return a dictionary format representation of the QASM Qobj.

Note this dict is not in the json wire format expected by IBMQ and qobj specification because complex numbers are still of type complex. Also this may contain native numpy arrays. When serializing this output for use with IBMQ you can leverage a json encoder that converts these as expected. For example:

import json
import numpy
class QobjEncoder(json.JSONEncoder):
    def default(self, obj):
        if isinstance(obj, numpy.ndarray):
            return obj.tolist()
        if isinstance(obj, complex):
            return (obj.real, obj.imag)
        return json.JSONEncoder.default(self, obj)
json.dumps(qobj.to_dict(), cls=QobjEncoder)


A dictionary representation of the QasmQobj object

Return type


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