How can I slice a list in python using a theano scalar?

Question

    index = T.iscalar()
    train_function = theano.function(inputs = [index], outputs = [cost_function], updates = updates, 
                                givens = {
                                    x: train_set[0][index * batch_size: (index + 1) * batch_size],
                                    y: train_set[1][index * batch_size: (index + 1) * batch_size]
                                })

I am trying to follow a theano tutorial and trying to implement my own version of logistic regression. I have created a function that takes an integer input as an input and trains the model. train_set[0] is the entire matrix data, train_set[1] is the entire label data

X and Y are subsets of matrix and label data respectively

Since I am training batch wise, I need to remove batch samples from my data which I do using the index variable.

However I get the following error at this line of code

   TypeError: slice indices must be integers or None or have an __index__ method

I have also tried

   index = lscalar()

Any suggestions ?

Answer 1

Figured it out. Had to convert train_set[0] and test_set[0] into a theano array variable