How to turn a Pandas column into array and transpose it?

python arrays pandas numpy transpose
Stanleyrr picture Stanleyrr · Mar 29, 2018 · Viewed 19k times · Source

I have a Pandas dataframe called 'training_set' that resembles the screenshot below:

enter image description here

I try to turn the 'label' column into array and transpose it. I tried doing Y_train=np.asarray(training_set['label']) but what I got is a horizontal array that resembles the screenshot below, which is not what I want.

enter image description here

I want the array to display vertically just like the screenshot below (The screenshot has 2 variables per row. My desired output should only contain 1 variable, the 'label', per row.)

enter image description here

Any suggestion or help would be greatly appreciated!

Answer

cs95 picture cs95 · Mar 29, 2018

pandas >= 0.24

Use DataFrame.to_numpy(), the new Right Way to extract a numpy array:

training_set[['label']].to_numpy()

pandas < 0.24

Slice out your column as a single columned DataFrame (using [[...]]), not as a Series:

Y_train = np.asarray(training_set[['label']])

Or,

Y_train = training_set[['label']].values

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