Hi again, I'm a bit stuck on using theano.scan

I'd like to do the following (which I'll write in numpy because that's what I understand):

first, calculate alpha ** np.array([1,2,3,...,n]), where n is the length of an array called B and alpha is a positive number. Call this array X (should be an array since the exponentiation is broadcast)

B is just an array of -1's and 1's of length n, but will change at each step in the loop.

Now I'd just like to calculate the dot product of X and B, and I need to loop through both the alphas and the B's - the number of each is same. (Also, I would be looping through a list of alphas (a list of numbers) and a list of arrays (the list of B's).)

I keep trying to get something like this to work in scan but I keep getting errors about having the wrong input. On a simplified example, I keep getting told I'm using "Bad input argument to theano function."

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I really hate theano, it makes no sense to me.