ParameterExpression
class ParameterExpression(symbol_map, expr)
Bases: object
ParameterExpression class to enable creating expressions of Parameters.
Create a new ParameterExpression.
Not intended to be called directly, but to be instantiated via operations on other Parameter or ParameterExpression objects.
Parameters
- symbol_map (Dict[Parameter, [ParameterExpression, float, or int]]) – Mapping of
Parameterinstances to thesympy.Symbolserving as their placeholder in expr. - expr (sympy.Expr) – Expression of
sympy.Symbols.
Methods
arccos
ParameterExpression.arccos()
Arccos of a ParameterExpression
arcsin
ParameterExpression.arcsin()
Arcsin of a ParameterExpression
arctan
ParameterExpression.arctan()
Arctan of a ParameterExpression
assign
ParameterExpression.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
ParameterExpression.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
ParameterExpression.conjugate()
Return the conjugate.
Return type
ParameterExpression
cos
ParameterExpression.cos()
Cosine of a ParameterExpression
exp
ParameterExpression.exp()
Exponential of a ParameterExpression
gradient
ParameterExpression.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, float]
Returns
ParameterExpression representing the gradient of param_expr w.r.t. param
is_real
ParameterExpression.is_real()
Return whether the expression is real
log
ParameterExpression.log()
Logarithm of a ParameterExpression
sin
ParameterExpression.sin()
Sine of a ParameterExpression
subs
ParameterExpression.subs(parameter_map)
Returns a new Expression with replacement Parameters.
Parameters
parameter_map (Dict) – Mapping from Parameters in self to the ParameterExpression instances with which they should be replaced.
Raises
CircuitError –
- If parameter_map contains Parameters outside those in self. - If the replacement Parameters in parameter_map would result in a name conflict in the generated expression.
Return type
ParameterExpression
Returns
A new expression with the specified parameters replaced.
tan
ParameterExpression.tan()
Tangent of a ParameterExpression
Attributes
parameters
Returns a set of the unbound Parameters in the expression.
Return type
Set