Question

I have done EDA on this white whine dataset and I am trying to find 3 predictors of quality and conduct linear regression on them.

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt

%matplotlib inline

wine = "~/Desktop/datasets/winequality-white.csv"
# Load the data
df = pd.read_csv(wine,sep=";")
df.head()

# Look at the information regarding its columns.
df.info()
# non-null floats also validated by √null_release_mask = df['fixed 
acidity'].isnull()

我正在尝试进行火车测试，并选择3个预测变量来预测质量

 from sklearn.model_selection import train_test_split

 X = df[["alcohol", "pH","free sulfur dioxide"]]
 y = df["quality"]

 X_train, X_test, y_train, y_test = train_test_split(X, y, 
 test_size=0.3, random_state=42)

 print(len(X_train), len(X_test))
 print(len(y_train), len(y_test))`
 from sklearn.linear_model import LinearRegression

 model = LinearRegression()

 model.fit(X_train,y_train)


import numpy as np

x_values_to_plot = np.linspace(0, df[["alcohol", "pH","free sulfur 
dioxide"]].max(), 15)
y_values_to_plot = (x_values_to_plot * model.coef_) + model.intercept_

fig, ax = plt.subplots(figsize=(6,6))

ax.scatter(df[["alcohol", "pH","free sulfur dioxide"]], df["quality"], 
label="data", alpha=0.2)
ax.plot(x_values_to_plot, y_values_to_plot, label="regression_line of 
white wines", c="r")
ax.legend(loc="best")

plt.show()

但是我收到此错误：

    ---------------------------------------------------------------------------
ValueError                                Traceback (most recent call 
 last)
<ipython-input-68-c52d735932ab> in <module>()
  1 import numpy as np
  2 
----> 3 x_values_to_plot = np.linspace(0, df[["alcohol", "pH","free 
sulfur dioxide"]].max(), 15)
      4 y_values_to_plot = (x_values_to_plot * model.coef_) + 
model.intercept_
      5 

~/anaconda3/lib/python3.7/site-packages/numpy/core/function_base.py in 
linspace(start, stop, num, endpoint, retstep, dtype)
    122     if num > 1:
    123         step = delta / div
--> 124         if step == 0:
    125             # Special handling for denormal numbers, gh-5437
    126             y /= div

 *ValueError: The truth value of an array with more than one element 
 is 
  ambiguous. Use a.any() or a.all()*

任何帮助将不胜感激，我是StackOverflow的新手，所以请留心问题的格式，并让我知道我可以改进的地方。谢谢

Answer 1

此特定错误与此代码段有关

x_values_to_plot = np.linspace(0, df[["alcohol", "pH","free sulfur dioxide"]].max(), 15)

自

df[["alcohol", "pH","free sulfur dioxide"]].max()

将返回三个值，酒精，pH和游离SO2的最大值。您可以通过添加另一个.max（）来解决此问题，假设这是您要尝试的操作，它将选择这三个最大值中的最大值。

回归模型下面的部分还存在其他一些问题。您到底想表达什么？您总是可以尝试使用seaborn，这对于这些类型的可视化很有用。

使用1个目标（质量）的3个预测变量的Python（ML）线性回归

1 个答案: