Flaky test: test_distributions_random.TestMvNormal

[MarcoGorelli]

Sporadic failure:

=================================== FAILURES ===================================
_____________ TestMvNormal.test_with_chol_rv[(10, 3)-(10, 3)-(1,)] _____________

self = <pymc3.tests.test_distributions_random.TestMvNormal object at 0x7f17ff33f040>
sample_shape = (10, 3), dist_shape = (10, 3), mu_shape = (1,)

    @pytest.mark.parametrize(
        ["sample_shape", "dist_shape", "mu_shape"],
        generate_shapes(include_params=False, xfail=True),
        ids=str,
    )
    def test_with_chol_rv(self, sample_shape, dist_shape, mu_shape):
        with pm.Model() as model:
            mu = pm.Normal("mu", 0.0, 1.0, shape=mu_shape)
            sd_dist = pm.Exponential.dist(1.0, shape=3)
            chol, corr, stds = pm.LKJCholeskyCov(
                "chol_cov", n=3, eta=2, sd_dist=sd_dist, compute_corr=True
            )
            mv = pm.MvNormal("mv", mu, chol=chol, shape=dist_shape)
>           prior = pm.sample_prior_predictive(samples=sample_shape)

pymc3/tests/test_distributions_random.py:1633: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
pymc3/sampling.py:1938: in sample_prior_predictive
    values = draw_values([model[name] for name in names], size=samples)
pymc3/distributions/distribution.py:783: in draw_values
    value = _draw_value(next_, point=point, givens=temp_givens, size=size)
pymc3/distributions/distribution.py:947: in _draw_value
    return param.random(point=point, size=size)
pymc3/model.py:111: in __call__
    return getattr(self.obj, self.method_name)(*args, **kwargs)
pymc3/distributions/multivariate.py:262: in random
    mu, param = draw_values([self.mu, param_attribute], point=point, size=size)
pymc3/distributions/distribution.py:826: in draw_values
    value = _draw_value(param, point=point, givens=givens.values(), size=size)
pymc3/distributions/distribution.py:998: in _draw_value
    output = func(*input_vals)
/usr/share/miniconda/envs/pymc3-dev-py38/lib/python3.8/site-packages/numpy/lib/function_base.py:2108: in __call__
    return self._vectorize_call(func=func, args=vargs)
/usr/share/miniconda/envs/pymc3-dev-py38/lib/python3.8/site-packages/numpy/lib/function_base.py:2182: in _vectorize_call
    res = self._vectorize_call_with_signature(func, args)
/usr/share/miniconda/envs/pymc3-dev-py38/lib/python3.8/site-packages/numpy/lib/function_base.py:2211: in _vectorize_call_with_signature
    broadcast_shape, dim_sizes = _parse_input_dimensions(
/usr/share/miniconda/envs/pymc3-dev-py38/lib/python3.8/site-packages/numpy/lib/function_base.py:1873: in _parse_input_dimensions
    _update_dim_sizes(dim_sizes, arg, core_dims)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

dim_sizes = {}, arg = array(-1.), core_dims = ('i_0_0',)

    def _update_dim_sizes(dim_sizes, arg, core_dims):
        """
        Incrementally check and update core dimension sizes for a single argument.
    
        Arguments
        ---------
        dim_sizes : Dict[str, int]
            Sizes of existing core dimensions. Will be updated in-place.
        arg : ndarray
            Argument to examine.
        core_dims : Tuple[str, ...]
            Core dimensions for this argument.
        """
        if not core_dims:
            return
    
        num_core_dims = len(core_dims)
        if arg.ndim < num_core_dims:
>           raise ValueError(
                '%d-dimensional argument does not have enough '
                'dimensions for all core dimensions %r'
                % (arg.ndim, core_dims))
E           ValueError: 0-dimensional argument does not have enough dimensions for all core dimensions ('i_0_0',)

/usr/share/miniconda/envs/pymc3-dev-py38/lib/python3.8/site-packages/numpy/lib/function_base.py:1836: ValueError

[Sayam753]

That's weird. I am on current master 4fd56fd and the test passes locally on my mac. @MarcoGorelli how can I reproduce this?

[MarcoGorelli]

@Sayam753 I can't reproduce it either, but it happened in this run https://github.com/pymc-devs/pymc3/runs/1529222002

[ricardoV94]

Test has been refactored, closing this one