pymc.draw#

pymc.draw(vars, draws=1, random_seed=None, **kwargs)[source]#

Draw samples for one variable or a list of variables

Parameters
varsVariable or iterable of Variable

A variable or a list of variables for which to draw samples.

drawsint, default 1

Number of samples needed to draw.

random_seedint, RandomState or Generator, optional

Seed for the random number generator.

**kwargsdict, optional

Keyword arguments for pymc.aesara.compile_pymc().

Returns
list of ndarray

A list of numpy arrays.

Examples

import pymc as pm

# Draw samples for one variable
with pm.Model():
    x = pm.Normal("x")
x_draws = pm.draw(x, draws=100)
print(x_draws.shape)

# Draw 1000 samples for several variables
with pm.Model():
    x = pm.Normal("x")
    y = pm.Normal("y", shape=10)
    z = pm.Uniform("z", shape=5)
num_draws = 1000
# Draw samples of a list variables
draws = pm.draw([x, y, z], draws=num_draws)
assert draws[0].shape == (num_draws,)
assert draws[1].shape == (num_draws, 10)
assert draws[2].shape == (num_draws, 5)