Help with python HMMs

Hi Everybody.

So, I would like to learn how to use Hidden Markov Models (HMMs) in Python. It seems that hmmlearn is among the few functional libraries out there.

I tried implementing a basic example found here. It looks like this example has been implemented using the sklearn package that is now deprecated and is succeeded by hmmlearn.

Below is my attempt to port it to hmmlearn.

Code:

from __future__ import division
import numpy as np
from hmmlearn import hmm 

states = ["Rainy", "Sunny"]
n_states = len(states)

observations = ["walk", "shop", "clean"]
n_observations = len(observations)

start_probability = np.array([0.6, 0.4])

transition_probability = np.array([
  [0.7, 0.3],
  [0.4, 0.6]
])

emission_probability = np.array([
  [0.1, 0.4, 0.5],
  [0.6, 0.3, 0.1]
])

model = hmm.MultinomialHMM(n_components=n_states)
model.startprob_ = start_probability
model.transmat_ =  transition_probability
model.emissionprob_ =  emission_probability

# predict a sequence of hidden states based on visible states
bob_says = [0, 2, 1, 1, 2, 0]
logprob, alice_hears = model.decode(bob_says, algorithm="viterbi")
print "Bob says:", ", ".join(map(lambda x: observations[x], bob_says))
print "Alice hears:", ", ".join(map(lambda x: states[x], alice_hears))

The problem is that when I run it, I get the following error

Code:

usr/lib64/python2.7/site-packages/sklearn/utils/validation.py:386: DeprecationWarning: Passing 1d arrays as data is deprecated in 0.17 and willraise ValueError in 0.19. Reshape your data either using X.reshape(-1, 1) if your data has a single feature or X.reshape(1, -1) if it contains a single sample.
  DeprecationWarning)
Traceback (most recent call last):
  File "hmmbobalice.py", line 30, in <module>
    logprob, alice_hears = model.decode(bob_says, algorithm="viterbi")
  File "/usr/lib64/python2.7/site-packages/hmmlearn/base.py", line 313, in decode
    state_sequence[i:j] = state_sequenceij
ValueError: could not broadcast input array from shape (6) into shape (1)

It would be great if somebody could shed some light on this (or suggest a better library for Python!)

Thank you!

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Help with python HMMs