Pandas + sklearn线性回归失败

时间:2015-11-20 09:18:13

标签: python pandas scikit-learn

我正在尝试在Python中实现一些线性回归模型。请参阅下面的代码,我用它来进行线性回归。

import pandas
salesPandas = pandas.DataFrame.from_csv('home_data.csv')

# check the shape of the DataFrame (rows, columns)
salesPandas.shape
(21613, 20)

from sklearn.cross_validation import train_test_split

train_dataPandas, test_dataPandas = train_test_split(salesPandas, train_size=0.8, random_state=1)

from sklearn.linear_model import LinearRegression

reg_model_Pandas = LinearRegression()

print type(train_dataPandas)
print train_dataPandas.shape
<class 'pandas.core.frame.DataFrame'>
(17290, 20)

print type(train_dataPandas['price'])
print train_dataPandas['price'].shape
<class 'pandas.core.series.Series'>
(17290L,)

X = train_dataPandas
y = train_dataPandas['price']
reg_model_Pandas.fit(X, y)

执行上面的python代码后,出现以下错误:

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-11-dc363e199032> in <module>()
      3 X = train_dataPandas
      4 y = train_dataPandas['price']
----> 5 reg_model_Pandas.fit(X, y)

C:\Users\...\AppData\Local\Continuum\Anaconda2\lib\site-packages\sklearn\linear_model\base.py in fit(self, X, y, n_jobs)
    374             n_jobs_ = self.n_jobs
    375         X, y = check_X_y(X, y, accept_sparse=['csr', 'csc', 'coo'],
--> 376                          y_numeric=True, multi_output=True)
    377 
    378         X, y, X_mean, y_mean, X_std = self._center_data(

C:\Users\...\AppData\Local\Continuum\Anaconda2\lib\site-packages\sklearn\utils\validation.py in check_X_y(X, y, accept_sparse, dtype, order, copy, force_all_finite, ensure_2d, allow_nd, multi_output, ensure_min_samples, ensure_min_features, y_numeric)
    442     X = check_array(X, accept_sparse, dtype, order, copy, force_all_finite,
    443                     ensure_2d, allow_nd, ensure_min_samples,
--> 444                     ensure_min_features)
    445     if multi_output:
    446         y = check_array(y, 'csr', force_all_finite=True, ensure_2d=False,

C:\Users\...\AppData\Local\Continuum\Anaconda2\lib\site-packages\sklearn\utils\validation.py in check_array(array, accept_sparse, dtype, order, copy, force_all_finite, ensure_2d, allow_nd, ensure_min_samples, ensure_min_features)
    342             else:
    343                 dtype = None
--> 344         array = np.array(array, dtype=dtype, order=order, copy=copy)
    345         # make sure we actually converted to numeric:
    346         if dtype_numeric and array.dtype.kind == "O":

ValueError: invalid literal for float(): 20140610T000000

train_dataPandas.info()

的输出
<class 'pandas.core.frame.DataFrame'>
Int64Index: 17290 entries, 4058200630 to 1762600320
Data columns (total 20 columns):
date             17290 non-null object
price            17290 non-null int64
bedrooms         17290 non-null int64
bathrooms        17290 non-null float64
sqft_living      17290 non-null int64
sqft_lot         17290 non-null int64
floors           17290 non-null float64
waterfront       17290 non-null int64
view             17290 non-null int64
condition        17290 non-null int64
grade            17290 non-null int64
sqft_above       17290 non-null int64
sqft_basement    17290 non-null int64
yr_built         17290 non-null int64
yr_renovated     17290 non-null int64
zipcode          17290 non-null int64
lat              17290 non-null float64
long             17290 non-null float64
sqft_living15    17290 non-null int64
sqft_lot15       17290 non-null int64
dtypes: float64(4), int64(15), object(1)
memory usage: 2.8+ MB

2 个答案:

答案 0 :(得分:1)

感谢EdChum,迄今为止的解决方案如下:

  1. 首先我上传了数据
  2. salesPandas.info()正在向我展示
  3. Int64Index: 21613 entries, 7129300520 to 1523300157
    Data columns (total 20 columns):
    date 21613 non-null object
    

    这不好因为sklearn,不能使用日期作为对象

    1. 如果我执行salesPandas.head(),则第一个图案的日期为
    2.   

      20141013T000000

      你看到了T? ...坏

      1. sklearn.linear_model.LinearRegression().fit()想拥有npy数组(Pandas构建于numpy上,因此DataFrame也是一个numpy数组)

      2. 首先将对象转换为datetime,然后将其转换为数字

      3.   

        salesPandas ['date'] = pandas.to_datetime(salesPandas ['date'],   格式= '%Y%米%的dT%H%M%S')

             

        salesPandas ['date'] = pandas.to_numeric(salesPandas ['date'])

        1. 如果你那么

          reg_model_Pandas.fit(X,y)

        2. 它有效

答案 1 :(得分:1)

根据您的数据,另一种可能的解决方案是在从文件中读取日期时指定parse_dates

import pandas
salesPandas = pandas.read_csv('home_data.csv', parse_dates=['date'])

这会有所帮助的原因是当你传递你的数据时你可以把它分解成月,小时,天。这假设您的大部分数据都集中在前面提到的数据上,而不是多年(即您的独特年份总数约为3-4)

在此处,您可以使用Datetimelike Properties并通过执行salesPandas['date'].dt.month来调用月份,然后按天和小时相应地更换它。