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I am creating a very rudimentary "Address Book" program in Python. I am grabbing contact data from a CSV file, the contents of which looks like the following example:

Name,Phone,Company,Email
Elon Musk,454-6723,SpaceX,emusk@spacex.com
Larry Page,853-0653,Google,lpage@gmail.com
Tim Cook,133-0419,Apple,tcook@apple.com
Steve Ballmer,456-7893,Developers!,sballmer@bluescreen.com

I am trying to format the output so that it looks cleaner and more readable, i.e. everything lined up in rows and columns, like this:

Name:        Phone:        Company:        Email:        
Elon Musk    454-6723      SpaceX          emusk@spacex.com

My current code is as follows:

f = open("contactlist.csv")
csv_f = csv.reader(f)
for row in csv_f:
    print(row)

Which naturally due to lack of formatting, produces this, which still looks very unclean.

['Name', 'Phone', 'Company', 'Email']
['Elon Musk', '454-6723', 'SpaceX', 'emusk@spacex.com']
['Larry Page', '853-0653', 'Google', 'lpage@gmail.com']
['Tim Cook', '133-0419', 'Apple', 'tcook@apple.com']
['Steve Ballmer', '456-7893', 'Developers!', 'sballmer@bluescreen.com']

Any tips on how to produce a cleaner output would be greatly appreciated, as I am beginner and I find all of this quite confusing. Many thanks in advance.

shaneybrainy13
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2 Answers2

16

You could use format to left justify your output. For example,

f = open("contactlist.csv")
csv_f = csv.reader(f)
for row in csv_f:
    print('{:<15}  {:<15}  {:<20} {:<25}'.format(*row))

Output:

Name             Phone            Company              Email                    
Elon Musk        454-6723         SpaceX               emusk@spacex.com         
Larry Page       853-0653         Google               lpage@gmail.com          
Tim Cook         133-0419         Apple                tcook@apple.com          
Steve Ballmer    456-7893         Developers!          sballmer@bluescreen.com

You can read more about format here. The < symbol left-aligns the text, and the number specifies the width of the string. Each {} can include a positional argument before the colon : - if they are omitted, the strings will appear in the order of the arguments in the unpacked list row.

zarak
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2

There are a few python modules for creating tables through plain text, e.g. tabulate and prettytable. With tabulate the printing becomes a one-liner:

from tabulate import tabulate
f = open("contactlist.csv")
csv_f = csv.reader(f)
print(tabulate(csv_f, headers='firstrow'))

The output looks like this:

Name           Phone     Company      Email
-------------  --------  -----------  -----------------------
Elon Musk      454-6723  SpaceX       emusk@spacex.com
Larry Page     853-0653  Google       lpage@gmail.com
Tim Cook       133-0419  Apple        tcook@apple.com
Steve Ballmer  456-7893  Developers!  sballmer@bluescreen.com

You can also specify among a bunch of formatting options with the tablefmt keyword. The output of print(tabulate(csv_f,headers='firstrow', tablefmt='pipe')) for example corresponds to markdown table format:

| Name          | Phone    | Company     | Email                   |
|---------------|----------|-------------|-------------------------|
| Elon Musk     | 454-6723 | SpaceX      | emusk@spacex.com        |
| Larry Page    | 853-0653 | Google      | lpage@gmail.com         |
| Tim Cook      | 133-0419 | Apple       | tcook@apple.com         |
| Steve Ballmer | 456-7893 | Developers! | sballmer@bluescreen.com |
Nuighon
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