Vfrdtyky

I'm trying to evaluate a theano TensorValue expression:

import pymc3

import numpy as np

with pymc3.Model():

    growth = pymc3.Normal('growth_%s' % 'some_name', 0, 10)



x = np.arange(4)

(x * growth).eval()

but get the error

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

  File "/home/danna/.virtualenvs/lib/python2.7/site-packages/theano/gof/graph.py", line 522, in eval

    self._fn_cache[inputs] = theano.function(inputs, self)

  File "/home/danna/.virtualenvs/lib/python2.7/site-packages/theano/compile/function.py", line 317, in function

    output_keys=output_keys)

  File "/home/danna/.virtualenvs/lib/python2.7/site-packages/theano/compile/pfunc.py", line 486, in pfunc

    output_keys=output_keys)

  File "/home/danna/.virtualenvs/lib/python2.7/site-packages/theano/compile/function_module.py", line 1839, in orig_function

    name=name)

  File "/home/danna/.virtualenvs/lib/python2.7/site-packages/theano/compile/function_module.py", line 1487, in __init__

    accept_inplace)

  File "/home/danna/.virtualenvs/lib/python2.7/site-packages/theano/compile/function_module.py", line 181, in std_fgraph

    update_mapping=update_mapping)

  File "/home/danna/.virtualenvs/lib/python2.7/site-packages/theano/gof/fg.py", line 175, in __init__

    self.__import_r__(output, reason="init")

  File "/home/danna/.virtualenvs/lib/python2.7/site-packages/theano/gof/fg.py", line 346, in __import_r__

    self.__import__(variable.owner, reason=reason)

  File "/home/danna/.virtualenvs/lib/python2.7/site-packages/theano/gof/fg.py", line 391, in __import__

    raise MissingInputError(error_msg, variable=r)

theano.gof.fg.MissingInputError: Input 0 of the graph (indices start from 0), used to compute InplaceDimShuffle{x}(growth_some_name), was not provided and not given a value. Use the Theano flag exception_verbosity='high', for more information on this error.

I tried
Can someone please help me see what the theano variables actually output?
Thank you!
I'm using Python 2.7 and theano 1.0.3

While PyMC3 distributions are TensorVariable objects, they don't technical have any values to be evaluated outside of sampling. If you want values, you have to at least run sampling on the model:

with pymc3.Model():

    growth = pymc3.Normal('growth', 0, 10)



    trace = pymc3.sample(10)



x = np.arange(4)

x[:, np.newaxis]*trace['growth'] 

If you want to view node values during sampling, you'd need to use theano.tensor.printing.Print objects. For more info, see the PyMC3 debugging tips.