小编Bal*_*r82的帖子

我关注了Pandas Dataframe:

In [66]: hdf.size()
Out[66]:
a           b
0           0.0          21004
            0.1         119903
            0.2         186579
            0.3         417349
            0.4         202723
            0.5         100906
            0.6          56386
            0.7           6080
            0.8           3596
            0.9           2391
            1.0           1963
            1.1           1730
            1.2           1663
            1.3           1614
            1.4           1309
...
186         0.2         15
            0.3          9
            0.4         21
            0.5          4
187         0.2          3
            0.3         10
            0.4         22
            0.5         10
188         0.0         11
            0.1         19
            0.2         20
            0.3         13
            0.4          7
            0.5          5
            0.6          1
Length: 4572, dtype: int64

你看,从0到188和每个组中的b从某个值到某个值.并且作为指定的Z值,对a/b的出现次数.

如何从分组数据框中获取countour或heatmap图？

我有这个(要求？): …

有没有解决方案可以打开 mp4 并覆盖图形（Matplotlib）或类似的东西？

像这样的东西

你们都知道这张图:

那里有一周中的某一天和一年中有某种活动的月份.假设我有这个Pandas数据帧:

In [87]: metadf2[['Week','Activity']]
Out[87]:
     Week Activity
weekday     
0    15  1.6
0    15  1.1
0    17  0.6
0    17  0.8
0    17  1.3
0    17  2.6
0    17  0.9
0    19  1.0
0    19  8.0
0    19  1.6
0    23  5.0
0    23  1.2
0    23  0.6
0    23  5.6
1    15  1.6
1    15  0.2
1    15  0.1
1    15  0.1
1    15  0.4
1    17  12.2
1    19  10.2
1    19  1.6
2    13  1.7
2    14 …

我尝试读取一个有效的Openstreetmaps API输出JSON字符串.

我使用以下代码:

import pandas as pd
import requests

# Links unten
minLat = 50.9549
minLon = 13.55232

# Rechts oben
maxLat = 51.1390
maxLon = 13.89873

osmrequest = {'data': '[out:json][timeout:25];(node["highway"="bus_stop"](%s,%s,%s,%s););out body;>;out skel qt;' % (minLat, minLon, maxLat, maxLon)}
osmurl = 'http://overpass-api.de/api/interpreter'
osm = requests.get(osmurl, params=osmrequest)

osmdata = osm.json()

osmdataframe = pd.read_json(osmdata)

抛出以下错误:

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-66-304b7fbfb645> in <module>()
----> 1 osmdataframe = pd.read_json(osmdata)

/Users/paul/anaconda/lib/python2.7/site-packages/pandas/io/json.pyc in read_json(path_or_buf, orient, typ, dtype, convert_axes, convert_dates, …

我想在csv文件中写一些随机样本数据,直到它大到1GB.以下代码正在运行:

import numpy as np
import uuid
import csv
import os
outfile = 'data.csv'
outsize = 1024 # MB
with open(outfile, 'ab') as csvfile:
    wtr = csv.writer(csvfile)
    while (os.path.getsize(outfile)//1024**2) < outsize:
        wtr.writerow(['%s,%.6f,%.6f,%i' % (uuid.uuid4(), np.random.random()*50, np.random.random()*50, np.random.randint(1000))])    

如何加快速度？