ValueError: Expected 2D array, got scalar array instead: array=750

Question

import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
import seaborn as sns
sns.set()
from sklearn.linear_model import LinearRegression

data=pd.read_csv('real_estate_price_size.csv')
y=data['price']
x=data['size']
y.shape
x.shape

两个输出相同 (100,)

x_matrix = x.values.reshape(-1,1)
reg = LinearRegression()
reg.fit(x_matrix,y)    
reg.predict(750)

当我运行出现此错误时

ValueError: Expected 2D array, got scalar array instead:
array=750.
Reshape your data either using array.reshape(-1, 1) if your data has a single feature or 
array.reshape(1, -1) if it contains a single sample.

我无法理解该怎么做我尝试重塑它但它没有成功。

和 (2) 之前我输入时

reg = LinearRegression()
reg.fit(x_matrix,y)

我曾经得到这样的输出

LinearRegression(copy_X=True, fit_intercept=True, n_jobs=1, normalize=False)

现在我只收到类似

的文字

 LinearRegression()

我们将不胜感激。

Answer 1

您缺少一个维度。您的预测输入应具有 (n_samples, n_features) 的形状。尝试这样的事情：

import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
import seaborn as sns
sns.set()
from sklearn.linear_model import LinearRegression

y=np.random.random((100, 1))
x=np.random.random((100, 1))

reg = LinearRegression()
reg.fit(x,y)
    
predict_input = np.array([[750]])
predict_input.shape
reg.predict(predict_input)

(1, 1)
array([[-26.07506481]])

ValueError: Expected 2D array, got scalar array instead: array=750

ValueError: Expected 2D array, got scalar array instead: array=750

python

numpy

pandas

sklearn-pandas