Printing Lists as Tabular Data

I am quite new to Python and I am now struggling with formatting my data nicely for printed output.

I have one list that is used for two headings, and a matrix that should be the contents of the table. Like so:

teams_list = ["Man Utd", "Man City", "T Hotspur"]
data = np.array([[1, 2, 1],
                 [0, 1, 0],
                 [2, 4, 2]])

Note that the heading names are not necessarily the same lengths. The data entries are all integers, though.

Now, I want to represent this in a table format, something like this:

            Man Utd   Man City   T Hotspur
  Man Utd         1          0           0
 Man City         1          1           0
T Hotspur         0          1           2

I have a hunch that there must be a data structure for this, but I cannot find it. I have tried using a dictionary and formatting the printing, I have tried for-loops with indentation and I have tried printing as strings.

I am sure there must be a very simple way to do this, but I am probably missing it due to lack of experience.

There are some light and useful python packages for this purpose:

1. tabulate: https://pypi.python.org/pypi/tabulate

from tabulate import tabulate
print(tabulate([['Alice', 24], ['Bob', 19]], headers=['Name', 'Age']))

Name      Age
------  -----
Alice      24
Bob        19

tabulate has many options to specify headers and table format.

print(tabulate([['Alice', 24], ['Bob', 19]], headers=['Name', 'Age'], tablefmt='orgtbl'))

| Name   |   Age |
|--------+-------|
| Alice  |    24 |
| Bob    |    19 |

2. PrettyTable: https://pypi.python.org/pypi/PrettyTable

from prettytable import PrettyTable
t = PrettyTable(['Name', 'Age'])
t.add_row(['Alice', 24])
t.add_row(['Bob', 19])
print(t)

+-------+-----+
|  Name | Age |
+-------+-----+
| Alice |  24 |
|  Bob  |  19 |
+-------+-----+

PrettyTable has options to read data from csv, html, sql database. Also you are able to select subset of data, sort table and change table styles.

3. texttable: https://pypi.python.org/pypi/texttable

from texttable import Texttable
t = Texttable()
t.add_rows([['Name', 'Age'], ['Alice', 24], ['Bob', 19]])
print(t.draw())

+-------+-----+
| Name  | Age |
+=======+=====+
| Alice | 24  |
+-------+-----+
| Bob   | 19  |
+-------+-----+

with texttable you can control horizontal/vertical align, border style and data types.

4. termtables: https://github.com/nschloe/termtables

import termtables as tt

string = tt.to_string(
    [["Alice", 24], ["Bob", 19]],
    header=["Name", "Age"],
    style=tt.styles.ascii_thin_double,
    # alignment="ll",
    # padding=(0, 1),
)
print(string)

+-------+-----+
| Name  | Age |
+=======+=====+
| Alice | 24  |
+-------+-----+
| Bob   | 19  |
+-------+-----+

with texttable you can control horizontal/vertical align, border style and data types.

Other options:

terminaltables Easily draw tables in terminal/console applications from a list of lists of strings. Supports multi-line rows.
asciitable Asciitable can read and write a wide range of ASCII table formats via built-in Extension Reader Classes.

Some ad-hoc code:

row_format ="{:>15}" * (len(teams_list) + 1)
print(row_format.format("", *teams_list))
for team, row in zip(teams_list, data):
    print(row_format.format(team, *row))

This relies on str.format() and the Format Specification Mini-Language.

>>> import pandas
>>> pandas.DataFrame(data, teams_list, teams_list)
           Man Utd  Man City  T Hotspur
Man Utd    1        2         1        
Man City   0        1         0        
T Hotspur  2        4         2

Python actually makes this quite easy.

Something like

for i in range(10):
    print '%-12i%-12i' % (10 ** i, 20 ** i)

will have the output

1           1           
10          20          
100         400         
1000        8000        
10000       160000      
100000      3200000     
1000000     64000000    
10000000    1280000000  
100000000   25600000000
1000000000  512000000000

The % within the string is essentially an escape character and the characters following it tell python what kind of format the data should have. The % outside and after the string is telling python that you intend to use the previous string as the format string and that the following data should be put into the format specified.

In this case I used "%-12i" twice. To break down each part:

'-' (left align)
'12' (how much space to be given to this part of the output)
'i' (we are printing an integer)

From the docs: https://docs.python.org/2/library/stdtypes.html#string-formatting

Updating Sven Marnach's answer to work in Python 3.4:

row_format ="{:>15}" * (len(teams_list) + 1)
print(row_format.format("", *teams_list))
for team, row in zip(teams_list, data):
    print(row_format.format(team, *row))

Printing Lists as Tabular Data

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