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pythonlistdynamic-list

How to update a dynamic list in python?


I had a list that has Business = ['Company name','Mycompany',Revenue','1000','Income','2000','employee','3000','Facilities','4000','Stock','5000'] , the output of the list structure is shown below:

Company        Mycompany
Revenue        1000
Income         2000
employee       3000
Facilities     4000
Stock          5000

The Dynamic list gets updated ***

for every iteration for the list and some of the items in the list is missing

***. for example execution 1 the list gets updated as below:

Company        Mycompany
Income         2000             #revenue is missing
employee       3000          
Facilities     4000
Stock          5000

In the above list the Revenue is removed from list as company has no revenue, in second example :

Company        Mycompany
Revenue        1000
Income         2000                
Facilities     4000              #Employee is missing
Stock          5000

In the above example 2 Employee is missing. How to create a output list that replaces the missing values with 0, in example 1 revenue is missing , hence I have to replace the output list with ['Revenue,'0'] at its position, for better understanding please find below

output list created for example 1: Revenue replaced with 0

Company Mycompany| **Revenue 0**| Income 2000| employee 3000| Facilities 4000| Stock 5000

Output list for example 2: employee is replaced with 0

Company Mycompany| Revenue 1000| Income 2000| **employee 0**| Facilities 4000| Stock 5000

How can I achieve the output list with replacing the output list with 0 on missing list items without changing the structure of list. My code so far:

       for line in Business:
        if 'Company' not in line:
            Business.insert( 0, 'company')
            Business.insert( 1, '0')
        if 'Revenue' not in line:
            #got stuck here
        if 'Income' not in line:
            #got stuck here
        if 'Employee' not in line:
            #got stuck here
        if 'Facilities' not in line:
            #got stuck here
        if 'Stock' not in line:
            #got stuck here

Thanks a lot in advance


Solution

  • As said in the comments, a dict is a much better data structure for the problem. If you really need the list, you could use a temporary dict like this:

    example = ['Company name','Mycompany','Income','2000','employee','3000','Facilities','4000','Stock','5000']
    template = ['Company name', 'Revenue', 'Income', 'employee', 'Facilities', 'Stock']
    
    # build a temporary dict
    exDict = dict(zip(example[::2], example[1::2]))
    
    # work on it
    result = []
    for i in template:
        result.append(i)
        if i in exDict.keys():
            result.append(exDict[i])
        else:
            result.append(0)
    

    A bit more efficient (but harder to understand for beginners) would be to create the temporary dict like this:

    i = iter(example)
    example_dict = dict(zip(i, i))
    

    This works because zip uses lazy evaluation.