Hi, I am currently doing Gaussian mixture examples. I found a part of the problem occurs in pm.Dirichlet, so I want to ask your ideas and perspective on this error… Sampling does not work at all… even though I did not add anything except pm.Dirichlet…

```
model_mixture = pm.Model()
with model_mixture:
pi = pm.Dirichlet('pi', a = np.ones(2))
trace = pm.sample()
```

Error:

ERROR (aesara.graph.rewriting.basic): Rewrite failure due to: constant_folding

ERROR (aesara.graph.rewriting.basic): node: SpecifyShape(TensorConstant{(3,) of 0.0}, TensorConstant{2})

ERROR (aesara.graph.rewriting.basic): TRACEBACK:

ERROR (aesara.graph.rewriting.basic): Traceback (most recent call last):

File “/Users/jinyoungko/anaconda3/lib/python3.9/site-packages/aesara/graph/rewriting/basic.py”, line 1933, in process_node

replacements = node_rewriter.transform(fgraph, node)

File “/Users/jinyoungko/anaconda3/lib/python3.9/site-packages/aesara/graph/rewriting/basic.py”, line 1092, in transform

return self.fn(fgraph, node)

File “/Users/jinyoungko/anaconda3/lib/python3.9/site-packages/aesara/tensor/rewriting/basic.py”, line 1142, in constant_folding

if r_shape is None and other_shape:

File “/Users/jinyoungko/anaconda3/lib/python3.9/site-packages/aesara/link/c/op.py”, line 103, in rval

thunk()

File “/Users/jinyoungko/anaconda3/lib/python3.9/site-packages/aesara/link/c/basic.py”, line 1788, in **call**

raise exc_value.with_traceback(exc_trace)

AssertionError: SpecifyShape: dim 0 of input has shape 3, expected 2.

If I increase the dimension of pm.Dirichlet by increasing np.ones(2) to np.ones(3), the error message just returns “AssertionError: SpecifyShape: dim 0 of input has shape 4, expected 3.”

It seems that the problem of pm.Dirichlet itself. Could you provide your perspectives?