使用 python 库可视化 JSON 数据

Question

I am visualising the json data using mathplotlib and pandas

  {
    "data_point": 0,
    "Add": 2977780,
    "Add_num": 38595
  },
  {
    "data_point": 1,
    "Add": 2809086,
    "Add_num": 36534
  },
  {
    "data_point": 2,
    "Add": 2825428,
    "Add_num": 36534
  },
  {
    "data_point": 3,
    "Add": 2826861,
    "Add_num": 36564
  }]

This is the data now i want to draw a graph with y-axis as value obtained from division of "Add" and "Add_num" (Add/Add_num) and "data_point" as x-axis. Is there a way to do this in python code or I need to process json data to add Add_avg field in json file(ie Add_avg = Add/Add_num)

Code to draw the graph

import json
import pandas as pd

a_file = open("./data.json", "r")
json_object = json.load(a_file)
a_file.close()
df = pd.DataFrame(json_object)
df.plot(x='data_point', y='Add',color='maroon', marker='o')
df.plot(x='data_point', y='Add_num',color='maroon', marker='o')

Answer 1

You can use matplotlib directly to plot, then you can do the calculations while plotting. Or you can indeed add another column:

import json
import pandas as pd
from matplotlib import pyplot as plt

js = """[ {
    "data_point": 0,
    "Add": 2977780,
    "Add_num": 38595
  },
  {
    "data_point": 1,
    "Add": 2809086,
    "Add_num": 36534
  },
  {
    "data_point": 2,
    "Add": 2825428,
    "Add_num": 36534
  },
  {
    "data_point": 3,
    "Add": 2826861,
    "Add_num": 36564
  }]"""

# Use loads instead of load since in my case the json is a string:
df = pd.DataFrame(json.loads(js))

# plot:
fig, ax = plt.subplots(1)
ax.plot(df['data_point'], df['Add']/df['Add_num'])
plt.show()

Or add a new column:

df['Add_avg'] = df['Add']  / df['Add_num']
df.plot(x='data_point', y='Add_avg', color='maroon', marker='o')
plt.show()