import cntk as C
import numpy as np
output = C.input_variable((1, 1, 1, 1), dtype=np.float32, needs_gradient=True, name='output')
target = C.input_variable((1, 2, 3, 1), dtype=np.float32, name='target')
dot_output = C.binary_cross_entropy(output, target)
convolution_function = C.combine(dot_output)
output_data = np.random.random((1, 1, 1, 1)).astype('float32')
target_data = np.random.random((1, 2, 3, 1)).astype('float32')
result = convolution_function.eval({output: output_data, target: target_data})
print(result)