热图海报中的日期轴

Question

一点信息:我对编程很新,这只是我第一个脚本的一小部分.这个特定部分的目标是显示一个seaborn热图,其中y轴为垂直深度,x轴为时间,科学测量强度为热函数.

如果在其他地方得到回答,我想道歉,但我的搜索能力一定让我失望.

sns.set()
nametag = 'Well_4_all_depths_capf'
Dp = D[D.well == 'well4']
print(Dp.date)


heat = Dp.pivot("depth",  "date", "capf")
### depth, date and capf are all columns of a pandas dataframe 

plt.title(nametag)

sns.heatmap(heat,  linewidths=.25)

plt.savefig('%s%s.png' % (pathheatcapf, nametag), dpi = 600)

这是从'print(Dp.date)打印的内容所以我非常确定数据框的格式是我想要的格式,特别是年,日,月.

0    2016-08-09
1    2016-08-09
2    2016-08-09
3    2016-08-09
4    2016-08-09
5    2016-08-09
6    2016-08-09
         ...    

但是,当我运行它时,日期轴始终打印出我不想要的空白时间(00:00等).有没有办法从日期轴中删除它们？

是否在上面的单元格中使用此函数扫描文件名并使用日期??? 使用datetime而不仅仅是日期函数是错误的吗？

D['date']=pd.to_datetime(['%s-%s-%s' %(f[0:4],f[4:6],f[6:8]) for f in             
D['filename']])

Answer 1

您必须在数据帧的日期系列中使用strftime函数才能正确绘制xtick标签:

import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
import seaborn as sns
from datetime import datetime, timedelta
import random

dates = [datetime.today() - timedelta(days=x * random.getrandbits(1)) for x in xrange(25)]
df = pd.DataFrame({'depth': [0.1,0.05, 0.01, 0.005, 0.001, 0.1, 0.05, 0.01, 0.005, 0.001, 0.1, 0.05, 0.01, 0.005, 0.001, 0.1, 0.05, 0.01, 0.005, 0.001, 0.1, 0.05, 0.01, 0.005, 0.001],\
 'date': dates,\
 'value': [-4.1808639999999997, -9.1753490000000006, -11.408113999999999, -10.50245, -8.0274750000000008, -0.72260200000000008, -6.9963940000000004, -10.536339999999999, -9.5440649999999998, -7.1964070000000007, -0.39225599999999999, -6.6216390000000001, -9.5518009999999993, -9.2924690000000005, -6.7605589999999998, -0.65214700000000003, -6.8852289999999989, -9.4557760000000002, -8.9364629999999998, -6.4736289999999999, -0.96481800000000006, -6.051482, -9.7846860000000007, -8.5710630000000005, -6.1461209999999999]})
pivot = df.pivot(index='depth', columns='date', values='value')

sns.set()
ax = sns.heatmap(pivot)
ax.set_xticklabels(df['date'].dt.strftime('%d-%m-%Y'))
plt.xticks(rotation=-90)

plt.show()