How to compare shape in PyTensor?

Questions v5
1

PyTensor graph can’t evaluate straight forward shape comparison right now (causing by this code), what is the workaround for now?

Code

import pytensor.tensor as pt

t = pt.as_tensor_variable([10])
if t.shape[0] > 10:
    print("Hello world!")
else:
    print("Hi!")

Output

TypeError: Variables do not support boolean operations.
2

For control flow, you want to use pt.switch. The comparison you do is otherwise fine:

x = pt.dmatrix('x')
y = pt.switch(x.shape[0] > 10, 1, 0)
y.eval({x:np.zeros((13, 10))})
>>> Out: 1
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