qiskit-documentation/docs/api/qiskit/0.24/qiskit.circuit.library.U1Ga...

368 lines
14 KiB
Plaintext
Raw Permalink Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

---
title: U1Gate
description: API reference for qiskit.circuit.library.U1Gate
in_page_toc_min_heading_level: 1
python_api_type: class
python_api_name: qiskit.circuit.library.U1Gate
---
<span id="qiskit-circuit-library-u1gate" />
# qiskit.circuit.library.U1Gate
<Class id="qiskit.circuit.library.U1Gate" isDedicatedPage={true} github="https://github.com/qiskit/qiskit/tree/stable/0.16/qiskit/circuit/library/standard_gates/u1.py" signature="U1Gate(theta, label=None)" modifiers="class">
Single-qubit rotation about the Z axis.
This is a diagonal gate. It can be implemented virtually in hardware via framechanges (i.e. at zero error and duration).
**Circuit symbol:**
```python
┌───────┐
q_0: ┤ U1(λ) ├
└───────┘
```
**Matrix Representation:**
$$
\begin{split}U1(\lambda) =
\begin{pmatrix}
1 & 0 \\
0 & e^{i\lambda}
\end{pmatrix}\end{split}
$$
**Examples:**
> $$
> U1(\lambda = \pi) = Z
> $$
>
> $$
> U1(\lambda = \pi/2) = S
> $$
>
> $$
> U1(\lambda = \pi/4) = T
> $$
<Admonition title="See also" type="note">
`RZGate`: This gate is equivalent to RZ up to a phase factor.
> $$
> U1(\lambda) = e^{i{\lambda}/2} RZ(\lambda)
> $$
`U3Gate`: U3 is a generalization of U2 that covers all single-qubit rotations, using two X90 pulses.
Reference for virtual Z gate implementation: [1612.00858](https://arxiv.org/abs/1612.00858)
</Admonition>
Create new U1 gate.
### \_\_init\_\_
<Function id="qiskit.circuit.library.U1Gate.__init__" signature="__init__(theta, label=None)">
Create new U1 gate.
</Function>
## Methods
| | |
| --------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------ |
| [`__init__`](#qiskit.circuit.library.U1Gate.__init__ "qiskit.circuit.library.U1Gate.__init__")(theta\[, label]) | Create new U1 gate. |
| [`add_decomposition`](#qiskit.circuit.library.U1Gate.add_decomposition "qiskit.circuit.library.U1Gate.add_decomposition")(decomposition) | Add a decomposition of the instruction to the SessionEquivalenceLibrary. |
| [`assemble`](#qiskit.circuit.library.U1Gate.assemble "qiskit.circuit.library.U1Gate.assemble")() | Assemble a QasmQobjInstruction |
| [`broadcast_arguments`](#qiskit.circuit.library.U1Gate.broadcast_arguments "qiskit.circuit.library.U1Gate.broadcast_arguments")(qargs, cargs) | Validation and handling of the arguments and its relationship. |
| [`c_if`](#qiskit.circuit.library.U1Gate.c_if "qiskit.circuit.library.U1Gate.c_if")(classical, val) | Add classical condition on register classical and value val. |
| [`control`](#qiskit.circuit.library.U1Gate.control "qiskit.circuit.library.U1Gate.control")(\[num\_ctrl\_qubits, label, ctrl\_state]) | Return a (mutli-)controlled-U1 gate. |
| [`copy`](#qiskit.circuit.library.U1Gate.copy "qiskit.circuit.library.U1Gate.copy")(\[name]) | Copy of the instruction. |
| [`inverse`](#qiskit.circuit.library.U1Gate.inverse "qiskit.circuit.library.U1Gate.inverse")() | Return inverted U1 gate ($U1(\lambda){\dagger} = U1(-\lambda)$) |
| [`is_parameterized`](#qiskit.circuit.library.U1Gate.is_parameterized "qiskit.circuit.library.U1Gate.is_parameterized")() | Return True .IFF. |
| [`mirror`](#qiskit.circuit.library.U1Gate.mirror "qiskit.circuit.library.U1Gate.mirror")() | DEPRECATED: use instruction.reverse\_ops(). |
| [`power`](#qiskit.circuit.library.U1Gate.power "qiskit.circuit.library.U1Gate.power")(exponent) | Creates a unitary gate as gate^exponent. |
| [`qasm`](#qiskit.circuit.library.U1Gate.qasm "qiskit.circuit.library.U1Gate.qasm")() | Return a default OpenQASM string for the instruction. |
| [`repeat`](#qiskit.circuit.library.U1Gate.repeat "qiskit.circuit.library.U1Gate.repeat")(n) | Creates an instruction with gate repeated n amount of times. |
| [`reverse_ops`](#qiskit.circuit.library.U1Gate.reverse_ops "qiskit.circuit.library.U1Gate.reverse_ops")() | For a composite instruction, reverse the order of sub-instructions. |
| [`to_matrix`](#qiskit.circuit.library.U1Gate.to_matrix "qiskit.circuit.library.U1Gate.to_matrix")() | Return a numpy.array for the U1 gate. |
| [`validate_parameter`](#qiskit.circuit.library.U1Gate.validate_parameter "qiskit.circuit.library.U1Gate.validate_parameter")(parameter) | Gate parameters should be int, float, or ParameterExpression |
## Attributes
| | |
| ---------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------- |
| [`decompositions`](#qiskit.circuit.library.U1Gate.decompositions "qiskit.circuit.library.U1Gate.decompositions") | Get the decompositions of the instruction from the SessionEquivalenceLibrary. |
| [`definition`](#qiskit.circuit.library.U1Gate.definition "qiskit.circuit.library.U1Gate.definition") | Return definition in terms of other basic gates. |
| [`duration`](#qiskit.circuit.library.U1Gate.duration "qiskit.circuit.library.U1Gate.duration") | Get the duration. |
| [`label`](#qiskit.circuit.library.U1Gate.label "qiskit.circuit.library.U1Gate.label") | Return gate label |
| [`params`](#qiskit.circuit.library.U1Gate.params "qiskit.circuit.library.U1Gate.params") | return instruction params. |
| [`unit`](#qiskit.circuit.library.U1Gate.unit "qiskit.circuit.library.U1Gate.unit") | Get the time unit of duration. |
### add\_decomposition
<Function id="qiskit.circuit.library.U1Gate.add_decomposition" signature="add_decomposition(decomposition)">
Add a decomposition of the instruction to the SessionEquivalenceLibrary.
</Function>
### assemble
<Function id="qiskit.circuit.library.U1Gate.assemble" signature="assemble()">
Assemble a QasmQobjInstruction
**Return type**
`Instruction`
</Function>
### broadcast\_arguments
<Function id="qiskit.circuit.library.U1Gate.broadcast_arguments" signature="broadcast_arguments(qargs, cargs)">
Validation and handling of the arguments and its relationship.
For example, `cx([q[0],q[1]], q[2])` means `cx(q[0], q[2]); cx(q[1], q[2])`. This method yields the arguments in the right grouping. In the given example:
```python
in: [[q[0],q[1]], q[2]],[]
outs: [q[0], q[2]], []
[q[1], q[2]], []
```
The general broadcasting rules are:
> * If len(qargs) == 1:
>
> ```python
> [q[0], q[1]] -> [q[0]],[q[1]]
> ```
>
> * If len(qargs) == 2:
>
> ```python
> [[q[0], q[1]], [r[0], r[1]]] -> [q[0], r[0]], [q[1], r[1]]
> [[q[0]], [r[0], r[1]]] -> [q[0], r[0]], [q[0], r[1]]
> [[q[0], q[1]], [r[0]]] -> [q[0], r[0]], [q[1], r[0]]
> ```
>
> * If len(qargs) >= 3:
>
> ```python
> [q[0], q[1]], [r[0], r[1]], ...] -> [q[0], r[0], ...], [q[1], r[1], ...]
> ```
**Parameters**
* **qargs** (`List`) List of quantum bit arguments.
* **cargs** (`List`) List of classical bit arguments.
**Return type**
`Tuple`\[`List`, `List`]
**Returns**
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.
</Function>
### c\_if
<Function id="qiskit.circuit.library.U1Gate.c_if" signature="c_if(classical, val)">
Add classical condition on register classical and value val.
</Function>
### control
<Function id="qiskit.circuit.library.U1Gate.control" signature="control(num_ctrl_qubits=1, label=None, ctrl_state=None)">
Return a (mutli-)controlled-U1 gate.
**Parameters**
* **num\_ctrl\_qubits** (*int*) number of control qubits.
* **label** (*str or None*) An optional label for the gate \[Default: None]
* **ctrl\_state** (*int or str or None*) control state expressed as integer, string (e.g. 110), or None. If None, use all 1s.
**Returns**
controlled version of this gate.
**Return type**
[ControlledGate](qiskit.circuit.ControlledGate "qiskit.circuit.ControlledGate")
</Function>
### copy
<Function id="qiskit.circuit.library.U1Gate.copy" signature="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**
[qiskit.circuit.Instruction](qiskit.circuit.Instruction "qiskit.circuit.Instruction")
</Function>
### decompositions
<Attribute id="qiskit.circuit.library.U1Gate.decompositions">
Get the decompositions of the instruction from the SessionEquivalenceLibrary.
</Attribute>
### definition
<Attribute id="qiskit.circuit.library.U1Gate.definition">
Return definition in terms of other basic gates.
</Attribute>
### duration
<Attribute id="qiskit.circuit.library.U1Gate.duration">
Get the duration.
</Attribute>
### inverse
<Function id="qiskit.circuit.library.U1Gate.inverse" signature="inverse()">
Return inverted U1 gate ($U1(\lambda){\dagger} = U1(-\lambda)$)
</Function>
### is\_parameterized
<Function id="qiskit.circuit.library.U1Gate.is_parameterized" signature="is_parameterized()">
Return True .IFF. instruction is parameterized else False
</Function>
### label
<Attribute id="qiskit.circuit.library.U1Gate.label">
Return gate label
**Return type**
`str`
</Attribute>
### mirror
<Function id="qiskit.circuit.library.U1Gate.mirror" signature="mirror()">
DEPRECATED: use instruction.reverse\_ops().
**Returns**
**a new instruction with sub-instructions**
reversed.
**Return type**
[qiskit.circuit.Instruction](qiskit.circuit.Instruction "qiskit.circuit.Instruction")
</Function>
### params
<Attribute id="qiskit.circuit.library.U1Gate.params">
return instruction params.
</Attribute>
### power
<Function id="qiskit.circuit.library.U1Gate.power" signature="power(exponent)">
Creates a unitary gate as gate^exponent.
**Parameters**
**exponent** (*float*) Gate^exponent
**Returns**
To which to\_matrix is self.to\_matrix^exponent.
**Return type**
[qiskit.extensions.UnitaryGate](qiskit.extensions.UnitaryGate "qiskit.extensions.UnitaryGate")
**Raises**
**CircuitError** If Gate is not unitary
</Function>
### qasm
<Function id="qiskit.circuit.library.U1Gate.qasm" signature="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];).
</Function>
### repeat
<Function id="qiskit.circuit.library.U1Gate.repeat" signature="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**
[qiskit.circuit.Instruction](qiskit.circuit.Instruction "qiskit.circuit.Instruction")
**Raises**
**CircuitError** If n \< 1.
</Function>
### reverse\_ops
<Function id="qiskit.circuit.library.U1Gate.reverse_ops" signature="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**
[qiskit.circuit.Instruction](qiskit.circuit.Instruction "qiskit.circuit.Instruction")
</Function>
### to\_matrix
<Function id="qiskit.circuit.library.U1Gate.to_matrix" signature="to_matrix()">
Return a numpy.array for the U1 gate.
</Function>
### unit
<Attribute id="qiskit.circuit.library.U1Gate.unit">
Get the time unit of duration.
</Attribute>
### validate\_parameter
<Function id="qiskit.circuit.library.U1Gate.validate_parameter" signature="validate_parameter(parameter)">
Gate parameters should be int, float, or ParameterExpression
</Function>
</Class>