# Week 3 Question 2

Hi, when i use the following code, i get the following output

# Size of input layer.

``````n_x = np.shape(X[0])
``````

The size of the input layer is: n_x = (30,)

The size of the input layer is: n_x = 1

Thank you

Try n_x = np.shape(X) or n_x = np.shape(X)[0]

The reason you are getting the output `n_x = (30,)` is because the `X` variable is a 30-dimensional array. To get the first dimension of the array, you can use the `X[0]` syntax. For example, the following code will print the first dimension of the `X` array:

X = np.array([1, 2, 3, 4, 5])
X[0]
1

In your case, you want to get the first dimension of the first element of the `X` array. To do this, you can use the following code:

n_x = np.shape(X[0])[0]
n_x
1

This code will print the value `1`, which is the first dimension of the first element of the `X` array.

For this reason, the following line would return what you have asked for:

n_x = np.shape(X)[0]

I hope this helps! Let me know if you have any other questions.

1 Like

It works now, thank you for the prompt assistance!