将值添加到创建的字典中的空键

Question

所以我基本上需要将一个值从 txt 文件添加到 output_dic 中的键，并且这两年都采用以下格式

我们的想法是从按行和列组织的 txt 中获取数据并对其进行处理以获取组织在以下输出中的数据


                                        2020                 2021        
Max Volume (Date)                       'value added'       'value2 added'
Min Volume (Date)

import matplotlib.pyplot as plt
import time     
import pandas as pd


def main(): 
    
    again = "y"     
    
    while again.lower() == 'y' or again.lower() == "yes":
    
    
    
        output_dic = {'Max Volume (Date)': ["", "", ""],
                  'Min Value (Date)' : ["" , "", ""],
                  'Lowest Open (Date)' : ["", "", ""] ,
                  'Highest Close (Date)' : ["", "", ""],
                  'Highest Monthly Average (Months)' : ["", "" , ""],
                  'Lowest Monthly Average (Months)' : ["", "", ""],
                  'Annual Average (Months)' : ["", "", ""]}
    
        print("\n{:^91}\n".format("Apple Stock Analysis 2020 and 2021"))
        print("{:^31} {:^20} {:^20}" .format(" ", "2020", "2021" , "total"))
        print("-" * 91)
        
        
        for k, v in output_dic.items():
                y2020, y2021, y2022 = v 
                print( "{:<31} {:^20} {:^20} {:^20}" .format(k , y2020, y2021, y2022))
        break
    
    
    output_dic.update({'Max Volume (Date)' :  })
    
    print(output_dic)

Answer 1

您可以通过简单地将值分配给键来向字典添加值，例如，如果键已经存在，则新值将替换旧值，例如：

output_dic['Max Volume (Date)'] = [0, 1, 2]

为了完整起见，我将编写一个示例代码片段，说明如何使用字典中已分配的值替换从 .txt 文件读取的值：

output_dic = {'Max Volume (Date)': ["", "", ""],
                'Min Value (Date)' : ["" , "", ""],
                'Lowest Open (Date)' : ["", "", ""] ,
                'Highest Close (Date)' : ["", "", ""],
                'Highest Monthly Average (Months)' : ["", "" , ""],
                'Lowest Monthly Average (Months)' : ["", "", ""],
                'Annual Average (Months)' : ["", "", ""]}

keys_list = ['Max Volume (Date)', 'Min Value (Date)', 'Lowest Open (Date)', 'Highest Close (Date)', 'Highest Monthly Average (Months)', 'Lowest Monthly Average (Months)', 'Annual Average (Months)']

input_file_address = 'E://file_name.txt'

with open(input_file_address, 'r') as input_file:
    index = 0
    for line in input_file:
        line_stripped = line.strip() # .txt files' lines usually end with \n and they could also have whitespace at the beginning by mistake, this line removes these issues
        
        if line_stripped == '': # if the line is empty, move to the next line
            continue
        
        line_splitted = line_stripped.split(' ') # If the values are separated by whitespace, this line would convert a string of for example 'a b c' to a list of ['a', 'b', 'c'] 
        
        key = keys_list[index]

        output_dic[key] = line_splitted

        index += 1

print(output_dic)

Assuming the .txt file is formatted as below:

value_1, value_2, value_3 ......................... .........................

where each line corresponds to a different parameter for example "Min Value" and so on.

最后我想提出一个建议：我认为 .txt 不是适合这些类型操作的文件格式，我个人更喜欢 .csv，它更容易解析，因为格式是通用的，不像 .txt 文件，任何人都可以以任何格式编写任何内容。

将值添加到创建的字典中的空键

Add a value to an empty key in a created dictionary

python

dictionary