06. AND Perceptron Quiz

AND Perceptron Quiz

What are the weights and bias for the AND perceptron?

Set the weights (weight1, weight2) and bias bias to the correct values that calculate AND operation as shown above.

In this case, there are two inputs as seen in the table above (let's call the first column input1 and the second column input2), and based on the perceptron formula, we can calculate the output.

First, the linear combination will be the sum of the weighted inputs: linear_combination = weight1*input1 + weight2*input2 then we can put this value into the biased Heaviside step function, which will give us our output (0 or 1):

Perceptron Formula

Perceptron Formula

Start Quiz:

import pandas as pd

# TODO: Set weight1, weight2, and bias
weight1 = 0.0
weight2 = 0.0
bias = 0.0


# DON'T CHANGE ANYTHING BELOW
# Inputs and outputs
test_inputs = [(0, 0), (0, 1), (1, 0), (1, 1)]
correct_outputs = [False, False, False, True]
outputs = []

# Generate and check output
for test_input, correct_output in zip(test_inputs, correct_outputs):
    linear_combination = weight1 * test_input[0] + weight2 * test_input[1] + bias
    output = int(linear_combination >= 0)
    is_correct_string = 'Yes' if output == correct_output else 'No'
    outputs.append([test_input[0], test_input[1], linear_combination, output, is_correct_string])

# Print output
num_wrong = len([output[4] for output in outputs if output[4] == 'No'])
output_frame = pd.DataFrame(outputs, columns=['Input 1', '  Input 2', '  Linear Combination', '  Activation Output', '  Is Correct'])
if not num_wrong:
    print('Nice!  You got it all correct.\n')
else:
    print('You got {} wrong.  Keep trying!\n'.format(num_wrong))
print(output_frame.to_string(index=False))

If you still need a hint, think of a concrete example like so:

Consider input1 and input2 both = 1, for an AND perceptron, we want the output to also equal 1! The output is determined by the weights and Heaviside step function such that 

output = 1, if  weight1*input1 + weight2*input2 + bias >= 0
or
output = 0, if  weight1*input1 + weight2*input2 + bias < 0

So, how can you choose the values for weights and bias so that if both inputs = 1, the output = 1?

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