pygsti.modelmembers.povms.tensorprodpovm
Defines the TensorProductPOVM class
Module Contents
Classes
A POVM that is effectively the tensor product of several other POVMs (which can be TP). |
- class pygsti.modelmembers.povms.tensorprodpovm.TensorProductPOVM(factor_povms, evotype='auto', state_space=None)
Bases:
pygsti.modelmembers.povms.povm.POVMA POVM that is effectively the tensor product of several other POVMs (which can be TP).
Parameters
- factor_povmslist of POVMs
POVMs that will be tensor-producted together.
- evotypeEvotype or str, optional
The evolution type. The special value “default” is equivalent to specifying the value of pygsti.evotypes.Evotype.default_evotype. The special value “auto” uses the evolution type of the first factor if there are more than zero factors.
- state_spaceStateSpace, optional
The state space for this POVM. This should be a space description compatible with the product of all the factors’ state spaces. If None a default compatible space will be chosen.
Initialize a new ModelMember
- property parameter_labels
An array of labels (usually strings) describing this model member’s parameters.
- property num_params
Get the number of independent parameters which specify this POVM.
Returns
- int
the number of independent parameters.
- keys()
An iterator over the effect (outcome) labels of this POVM.
- values()
An iterator over the effect SPAM vectors of this POVM.
- items()
An iterator over the (effect_label, effect_vector) items in this POVM.
- simplify_effects(prefix='')
Creates a dictionary of simplified effect vectors.
Returns a dictionary of effect POVMEffects that belong to the POVM’s parent Model - that is, whose gpindices are set to all or a subset of this POVM’s gpindices. Such effect vectors are used internally within computations involving the parent Model.
Parameters
- prefixstr
A string, usually identitying this POVM, which may be used to prefix the simplified gate keys.
Returns
OrderedDict of POVMEffects
- to_vector()
Extract a vector of the underlying gate parameters from this POVM.
Returns
- numpy array
a 1D numpy array with length == num_params().
- from_vector(v, close=False, dirty_value=True)
Initialize this POVM using a vector of its parameters.
Parameters
- vnumpy array
The 1D vector of POVM parameters. Length must == num_params().
- closebool, optional
Whether v is close to this POVM’s current set of parameters. Under some circumstances, when this is true this call can be completed more quickly.
- dirty_valuebool, optional
The value to set this object’s “dirty flag” to before exiting this call. This is passed as an argument so it can be updated recursively. Leave this set to True unless you know what you’re doing.
Returns
None
- depolarize(amount)
Depolarize this POVM by the given amount.
Parameters
- amountfloat or tuple
The amount to depolarize by. If a tuple, it must have length equal to one less than the dimension of the gate. All but the first element of each spam vector (often corresponding to the identity element) are multiplied by amount (if a float) or the corresponding amount[i] (if a tuple).
Returns
None