如何从 Matplotlib 文件中的 Excel 文件中 Plot 特定行？

Question

I have an Excel file that looks like this:

I would like to plot all 3 individuals' weight on Jan 1, 2020 on a bar chart to compare visually in Python using Matplotlib. How can I do this?

Answer 1

It's probably easiest done with pandas:

import pandas as pd
import datetime as dt


df = pd.read_excel('your_file_location', sheet_name='sheet_name', parse_dates=['Date'])
df = df.loc[df['Date'] == dt.date(year=2020, month=1, day=1)]
ax = df.plot.bar(df['Name'], df['Weight'])

Here we first load data from a specific sheet of your excel file (you can omit sheet_name argument if your excel file has only a single sheet), then we filter data to show only records from a specific date and then plot with names on x-axis and weight on y-axis.

Answer 2

import pandas as pd
import matplotlib.pyplot as plt

df = pd.read_csv('C:\\Desktop\\file.csv', index_col = 'Date', 
parse_dates = True)  #importing data to python and making date column as 
index
df['year'] = df.index.year #extracting year from index
data_20 = df[df['year'] == 2020] # Filtering out 2020 date
ax = data_20.plot(kind='bar',x='Name',y='Weight') #Plotting by name for 2020

To plot only for 2 people:

ax = data_20[data_20['Name'] != 'John Smith']
.plot(kind='bar',x='Name',y='Weight') #Plotting by name for 2020
ax.set_ylabel('Weights in lbs') #Labeling y-axis
ax.set_xlabel('Names') #Labeling x-axis
ax.set_title('Weights for 2020') # Adding the title

To make it pretty just add labels:

ax.set_ylabel('Weights in lbs') #Labeling y-axis
ax.set_xlabel('Names') #Labeling x-axis
ax.set_title('Weights for 2020'); # Adding the title