Transforming a data frame into a line array

Question

I used that to transform a data frame formed of just one column:

data = data_Y.values

However, I'm not happy with the results for the reason that I wanted all the data in a line, and instead I'm getting all the results on different lines. Do you have any idea how either transform:

[[1],[2]] into [1,2]

or directly getting a line vector from my dataframe?

Answer 1

A = np.array([[1],[2]])
B=A.flatten()
assert(np.all(B==np.array([1,2])))