sql3 = 'select sum(comment_num) as total_col,create_time from article GROUP BY create_time' df = pd.read_sql(sql3, conn) print(df) # 总数 # N = 22 # 宽度 width = 0.45 # ind = np.arange(N) plt.bar(df['create_time'], df['total_col'], width, color='r', label='total_col') plt.xlabel(u"发表日期") plt.ylabel(u"总评论数") plt.title(u"每日发表文章的总评论数直方分布图") plt.legend() plt.show()

df：

total_col create_time 0 2.0 2017-04-27 1 0.0 2017-05-09 2 3.0 2017-05-10 3 6.0 2017-05-11 4 3.0 2017-05-12 5 2.0 2017-05-13 6 1.0 2017-05-14 7 0.0 2017-05-15 8 5.0 2017-05-16 9 0.0 2017-05-17 10 1.0 2017-05-18 11 0.0 2017-05-19 12 6.0 2017-05-22 13 0.0 2017-05-24 14 1.0 2017-05-25 15 0.0 2017-05-26 16 6.0 2017-05-27 17 4.0 2017-05-29 18 16.0 2017-05-31 19 4.0 2017-06-02 20 2.0 2017-06-04 21 1.0 2017-06-05

错误：

Traceback (most recent call last): File "D:/PyCharm/py_scrapyjobbole/data_analysis.py", line 46, in  plt.bar(df['create_time'], df['total_col'], width, color='r', label='total_col') File "D:\python-3.5.2\lib\site-packages\matplotlib\pyplot.py", line 2704, in bar **kwargs) File "D:\python-3.5.2\lib\site-packages\matplotlib\__init__.py", line 1898, in inner return func(ax, *args, **kwargs) File "D:\python-3.5.2\lib\site-packages\matplotlib\axes\_axes.py", line 2105, in bar left = [left[i] - width[i] / 2. for i in xrange(len(left))] File "D:\python-3.5.2\lib\site-packages\matplotlib\axes\_axes.py", line 2105, in  left = [left[i] - width[i] / 2. for i in xrange(len(left))] TypeError: unsupported operand type(s) for -: 'datetime.date' and 'float'