尽管它更早工作，但代码中的键错误

Question

因此，由于人们的帮助，我在代码中修复了一个问题，但我得到了一个存在日期的键错误，这让我感到困惑。

这是错误的来源。 feature_matrix.loc["2019-06-04"]

该行接近评论#Predicting 的末尾。

附：有些格式很奇怪，因为我使用的是自动打印的 google colab

完整的代码如下所示：

data_urls = {
  "2014": "https://sitewebbixi.s3.amazonaws.com/uploads/docs/biximontrealrentals2014-f040e0.zip",
  "2015": "https://sitewebbixi.s3.amazonaws.com/uploads/docs/biximontrealrentals2015-69fdf0.zip",
  "2016": "https://sitewebbixi.s3.amazonaws.com/uploads/docs/biximontrealrentals2016-912f00.zip",
  "2017": "https://sitewebbixi.s3.amazonaws.com/uploads/docs/biximontrealrentals2017-d4d086.zip",
  "2018": "https://sitewebbixi.s3.amazonaws.com/uploads/docs/biximontrealrentals2018-96034e.zip",
  "2019": "https://sitewebbixi.s3.amazonaws.com/uploads/docs/biximontrealrentals2019-33ea73.zip",
}

"""# Load the data"""

"""
Load all the data

We will need:
- the requests package to surf the web, 
- the io package to read the data stream from the response,
- the zipfile package to manipulate the archive.
"""
import io
import pandas as pd
import requests
import zipfile


df = None
for year, url in data_urls.items():
  print("Processing {}".format(year))
  # Load the url
  response = requests.get(url)
  # Read the archive from the response
  archive = zipfile.ZipFile(io.BytesIO(response.content))
  # Loop over all the files in the archive
  for file in archive.namelist():
    # Check that we are looking at one of the files we want
    if not archive.getinfo(file).is_dir() and "Station" not in file:
      print("Loading data from: {}".format(file))
      # We will load the start_date column only to save on memory use
      try:
        current_length = len(df)
        df = df.append(
          pd.read_csv(archive.open(file), usecols=["start_date"]),
          ignore_index=True, 
        )
      except:
        current_length = 0
        df = pd.read_csv(archive.open(file), usecols=["start_date"])
      print(" > {} rows processed".format(len(df) - current_length))
  response.close()

"""# Convert to datetime"""

#This converts our dataframe to datetime
df["start_date"] = pd.to_datetime(df["start_date"])

df.describe()

df.info()

"""#Adding values that will help with the project"""

#This adds values for each date (without the hour)
df["date"] = df["start_date"].dt.date

#This adds values for each year from 2014 to 2019 to the dataframe
df["year"] = df["start_date"].dt.year

#This adds values for each day of the week to the dataframe
df["dayoftheweek"] = df["start_date"].dt.dayofweek

#This adds values for each day of the year to the dataframe
df["dayoftheyear"] = df["start_date"].dt.dayofyear

#This adds values for each month to the dataframe 
df["month"] = df["start_date"].dt.month

#This adds values for each week of the year to the dataframe
df["week"] = df["start_date"].dt.week

#This adds values for each hour (in a day) to the dataframe 
df["houroftheday"] = df["start_date"].dt.hour

"""# Visualizations to see the trends"""

#Get simple dataframes for each type of data in order to graph them
year_df = df["year"].value_counts(normalize=True).sort_index()
dayoftheweek_df = df["dayoftheweek"].value_counts(normalize=True).sort_index()
dayoftheyear_df = df["dayoftheyear"].value_counts(normalize=True).sort_index()
week_df = df["week"].value_counts(normalize=True).sort_index()
month_df = df["month"].value_counts(normalize=True).sort_index()
houroftheday_df = df["houroftheday"].value_counts(normalize=True).sort_index()
date_df = df["date"].value_counts(normalize=True).sort_index()

"""##Trends for each **year**"""

import matplotlib.pyplot as plt
plt.figure(figsize=[16,9], dpi=300)
plt.bar(year_df.index, year_df.values)
plt.show()

"""Usage goes higher each year, so that needs to be taken into account.

##Trends for each **day of the week**
"""

plt.figure(figsize=[16,9], dpi=300)
plt.bar(dayoftheweek_df.index, dayoftheweek_df.values)
plt.show()

"""In the graph above, 0 stands for Monday, 1 for Tuesday, so on and so forth.<br> So, BIXI usage is smaller during Saturday and Sunday. That seems to be a factor.

##Trends for each **month**
"""

plt.figure(figsize=[16,9], dpi=300)
plt.bar(month_df.index, month_df.values)
plt.show()

"""The trend is lower in the months where BIXI ends/starts and when it gets colder. Usage peaks in summer.

##Trends for each **day of the year**
"""

plt.figure(figsize=[16,9], dpi=300)
plt.bar(dayoftheyear_df.index, dayoftheyear_df.values)
plt.show()

"""The trend is similar to the months except, that on certain weekends (it's every seven days) we have a few drops.

## Trends per date
"""

plt.figure(figsize=[16,9], dpi=300)
plt.bar(date_df.index, date_df.values)
plt.show()

"""This is essentially a combination of the trend per year and the trend per day of the year together, but it uses the actual dates.

##Trends for each **week**
"""

plt.figure(figsize=[16,9], dpi=300)
plt.bar(week_df.index, week_df.values)
plt.show()

"""This trend is pretty much the monthly trend but with weeks (we see how the changes in usage happen in more detail)

## Trends for each **hour**
"""

plt.figure(figsize=[16,9], dpi=300)
plt.bar(houroftheday_df.index, houroftheday_df.values)
plt.show()

"""As we can see here, there's more bixi usage around rush hour periods (8 am & 3-6 pm), so we need to take that into account, since it is an important factor.

#Building the model
To build the model, we first need to set the target vector, then create the feature matrix and finally initializing the model that will make our predictions.

##Target vector
"""

target_df = df.groupby("date").size()
target_df

"""## Feature matrix
Here we will create the feature matrix
"""

#This needs to be done in order to be able to get the month name for the feature matrix
date_df["date"] = pd.to_datetime(df["date"])
date_df.describe

"""###Feature #1 : Day of the week"""

feature_df = pd.get_dummies(df.groupby("date").first(), columns=["dayoftheweek"], prefix="", prefix_sep="").loc[:,["0", "1", "2", "3", "4", "5", "6"]]
feature_df

"""###Feature #2 : Month of the year"""

for i, month in enumerate(pd.Series(feature_df.index).map(lambda x:pd._libs.tslibs.timestamps.Timestamp(x)).dt.month_name().unique(), 3):

    x = (pd.Series(pd.Series(feature_df.index).map(lambda x:pd._libs.tslibs.timestamps.Timestamp(x)).dt.month == (i+1))).astype(int)
    x.index = feature_df.index
    feature_df[month]=x
feature_df

"""##Dropping redundant columns"""

#This removes Monday and April, they will serve as our baseline
feature_matrix = feature_df.drop(columns=["0", "April"])

"""## Choosing a model
The model will be initialized and then used to make some predictions
"""

from sklearn.linear_model import LinearRegression

model = LinearRegression()

model.fit(feature_matrix , target_df)
parameters = pd.Series(model.coef_, index=feature_matrix.columns)
parameters

"""#Predicting"""

#June 4th 2016 was a Tuesday
feature_matrix.loc["2019-06-04"]

Answer 1

没关系，我用 feature_matrix.index = pd.to_datetime(feature_matrix.index) feature_matrix.loc['2019-06-04']