bayespy.nodes.Dirichlet

class bayespy.nodes.Dirichlet(*args, **kwargs)[source]

Node for Dirichlet random variables.

The node models a set of probabilities \{\pi_0, \ldots, \pi_{K-1}\} which satisfy \sum_{k=0}^{K-1} \pi_k = 1 and \pi_k \in [0,1] \ \forall k=0,\ldots,K-1.

p(\pi_0, \ldots, \pi_{K-1}) = \mathrm{Dirichlet}(\alpha_0, \ldots, \alpha_{K-1})

where \alpha_k are concentration parameters.

The posterior approximation has the same functional form but with different concentration parameters.

Parameters:

alpha ((...,K)-shaped array) – Prior counts \alpha_k

See also

Beta, Categorical, Multinomial, CategoricalMarkovChain

__init__(*args, **kwargs)

Methods

__init__(*args, **kwargs)

add_plate_axis(to_plate)

broadcasting_multiplier(plates, *args)

delete()

Delete this node and the children

get_gradient(rg)

Computes gradient with respect to the natural parameters.

get_mask()

get_moments()

get_parameters()

Return parameters of the VB distribution.

get_pdf_nodes()

get_riemannian_gradient()

Computes the Riemannian/natural gradient.

get_shape(ind)

has_plotter()

Return True if the node has a plotter

initialize_from_parameters(*args)

initialize_from_prior()

initialize_from_random()

Set the variable to a random sample from the current distribution.

initialize_from_value(x, *args)

load(filename)

logpdf(X[, mask])

Compute the log probability density function Q(X) of this node.

lower_bound_contribution([gradient, ...])

Compute E[ log p(X|parents) - log q(X) ]

lowerbound()

move_plates(from_plate, to_plate)

observe(x, *args[, mask])

Fix moments, compute f and propagate mask.

pdf(X[, mask])

Compute the probability density function of this node.

plot([fig])

Plot the node distribution using the plotter of the node

random()

Draw a random sample from the distribution.

save(filename)

set_parameters(x)

Set the parameters of the VB distribution.

set_plotter(plotter)

show()

Print the distribution using standard parameterization.

unobserve()

update([annealing])

Attributes

dims

plates

plates_multiplier

Plate multiplier is applied to messages to parents