Snapshot
class Snapshot(label, snapshot_type='statevector', num_qubits=0, num_clbits=0, params=None)
Bases: qiskit.circuit.instruction.Instruction
Simulator snapshot instruction.
Create new snapshot instruction.
Parameters
- label (str) – the snapshot label for result data.
- snapshot_type (str) – the type of the snapshot.
- num_qubits (int) – the number of qubits for the snapshot type [Default: 0].
- num_clbits (int) – the number of classical bits for the snapshot type [Default: 0].
- params (list or None) – the parameters for snapshot_type [Default: None].
Raises
ExtensionError – if snapshot label is invalid.
Methods
add_decomposition
Snapshot.add_decomposition(decomposition)
Add a decomposition of the instruction to the SessionEquivalenceLibrary.
assemble
Snapshot.assemble()
Assemble a QasmQobjInstruction
broadcast_arguments
Snapshot.broadcast_arguments(qargs, cargs)
Validation of the arguments.
Parameters
- qargs (List) – List of quantum bit arguments.
- cargs (List) – List of classical bit arguments.
Yields
Tuple(List, List) – A tuple with single arguments.
Raises
CircuitError – If the input is not valid. For example, the number of arguments does not match the gate expectation.
c_if
Snapshot.c_if(classical, val)
Set a classical equality condition on this instruction between the register or cbit classical and value val.
This is a setter method, not an additive one. Calling this multiple times will silently override any previously set condition; it does not stack.
copy
Snapshot.copy(name=None)
Copy of the instruction.
Parameters
name (str) – name to be given to the copied circuit, if None then the name stays the same.
Returns
a copy of the current instruction, with the name
updated if it was provided
Return type
inverse
Snapshot.inverse()
Special case. Return self.
is_parameterized
Snapshot.is_parameterized()
Return True .IFF. instruction is parameterized else False
qasm
Snapshot.qasm()
Return a default OpenQASM string for the instruction.
Derived instructions may override this to print in a different format (e.g. measure q[0] -> c[0];).
repeat
Snapshot.repeat(n)
Creates an instruction with gate repeated n amount of times.
Parameters
n (int) – Number of times to repeat the instruction
Returns
Containing the definition.
Return type
Raises
CircuitError – If n < 1.
reverse_ops
Snapshot.reverse_ops()
For a composite instruction, reverse the order of sub-instructions.
This is done by recursively reversing all sub-instructions. It does not invert any gate.
Returns
a new instruction with
sub-instructions reversed.
Return type
soft_compare
Snapshot.soft_compare(other)
Soft comparison between gates. Their names, number of qubits, and classical bit numbers must match. The number of parameters must match. Each parameter is compared. If one is a ParameterExpression then it is not taken into account.
Parameters
other (instruction) – other instruction.
Returns
are self and other equal up to parameter expressions.
Return type
bool
validate_parameter
Snapshot.validate_parameter(parameter)
Instruction parameters has no validation or normalization.
Attributes
condition_bits
Get Clbits in condition.
Return type
List[Clbit]
decompositions
Get the decompositions of the instruction from the SessionEquivalenceLibrary.
definition
Return definition in terms of other basic gates.
duration
Get the duration.
label
Return snapshot label
name
Return the name.
num_clbits
Return the number of clbits.
num_qubits
Return the number of qubits.
params
return instruction params.
snapshot_type
Return snapshot type
unit
Get the time unit of duration.