dibgerge / ml-coursera-python-assignments

Python assignments for the machine learning class by andrew ng on coursera with complete submission for grading capability and re-written instructions.
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misunderstanding of How to multiply delta with activation in back propagation NN #120

Open zizuo2050 opened 1 year ago

zizuo2050 commented 1 year ago

د I have a question in back propagation NN when compute for delta like 1 - 𝛿_3=(𝑎_3 - y) 2 - 𝛿_2=(Θ(2))𝑇𝛿_3∗𝑔′(𝑧(2)) 3 - Δ(𝑙)=Δ(𝑙)+𝛿(𝑙+1)(𝑎(𝑙))(𝑇) my question is how to compute for delta triangle which delta_2 = 25 element and a_1 = 400 element