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Parameter

Parameter(name) GitHub(opens in a new tab)

Bases: qiskit.circuit.parameterexpression.ParameterExpression

Parameter Class for variable parameters.

Create a new named Parameter.

Parameters

name (str) – name of the Parameter, used for visual representation. This can be any unicode string, e.g. “ϕ”.


Methods

arccos

Parameter.arccos()

Arccos of a ParameterExpression

arcsin

Parameter.arcsin()

Arcsin of a ParameterExpression

arctan

Parameter.arctan()

Arctan of a ParameterExpression

assign

Parameter.assign(parameter, value)

Assign one parameter to a value, which can either be numeric or another parameter expression.

Parameters

  • parameter (Parameter) – A parameter in this expression whose value will be updated.
  • value (Union[ParameterExpression, float]) – The new value to bind to.

Return type

ParameterExpression

Returns

A new expression parameterized by any parameters which were not bound by assignment.

bind

Parameter.bind(parameter_values)

Binds the provided set of parameters to their corresponding values.

Parameters

parameter_values (Dict) – Mapping of Parameter instances to the numeric value to which they will be bound.

Raises

  • CircuitError

    • If parameter_values contains Parameters outside those in self. - If a non-numeric value is passed in parameter_values.
  • ZeroDivisionError

    • If binding the provided values requires division by zero.

Return type

ParameterExpression

Returns

A new expression parameterized by any parameters which were not bound by parameter_values.

conjugate

Parameter.conjugate()

Return the conjugate.

Return type

ParameterExpression

cos

Parameter.cos()

Cosine of a ParameterExpression

exp

Parameter.exp()

Exponential of a ParameterExpression

gradient

Parameter.gradient(param)

Get the derivative of a parameter expression w.r.t. a specified parameter expression.

Parameters

param (Parameter) – Parameter w.r.t. which we want to take the derivative

Return type

Union[ParameterExpression, complex]

Returns

ParameterExpression representing the gradient of param_expr w.r.t. param or complex or float number

is_real

Parameter.is_real()

Return whether the expression is real

log

Parameter.log()

Logarithm of a ParameterExpression

sin

Parameter.sin()

Sine of a ParameterExpression

subs

Parameter.subs(parameter_map)

Substitute self with the corresponding parameter in parameter_map.

tan

Parameter.tan()

Tangent of a ParameterExpression


Attributes

name

Returns the name of the Parameter.

parameters

Returns a set of the unbound Parameters in the expression.

Return type

Set

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