Difference between python np.array shape (n,) and (n,1)

Created2022-07-08Updated2022-07-19

(n,)

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import numpy as np
shape_demo = np.array([1,2,3,4])
print(shape_demo)
print(shape_demo.shape)

(n,1)

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shape_demo_1 = np.array([[1],[2],[3],[4]])
print(shape_demo_1)
print(shape_demo_1.shape)

(2,4)

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shape_demo_2 = np.array([[1,2,3,4],[5,6,7,8]])
print(shape_demo_2)
print(shape_demo_2.shape)

sklearn datasets.make_regression

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import matplotlib.pyplot as plt
import numpy
from sklearn import datasets

#n_samples=10 n_features=1
regressionData = datasets.make_regression(10, 1, noise=10)

type of regressionData is tuple(2 items)
(ndarray with shape (10, 1), ndarray with shape (10,))

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type(regressionData)


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regressionData[0]


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regressionData[1]

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