[python] How do I output lists as a table in Jupyter notebook?

I know that I've seen some example somewhere before but for the life of me I cannot find it when googling around.

I have some rows of data:

data = [[1,2,3],
        [4,5,6],
        [7,8,9],
        ]

And I want to output this data in a table, e.g.

+---+---+---+
| 1 | 2 | 3 |
+---+---+---+
| 4 | 5 | 6 |
+---+---+---+
| 7 | 8 | 9 |
+---+---+---+

Obviously I could use a library like prettytable or download pandas or something but I'm very disinterested in doing that.

I just want to output my rows as tables in my Jupyter notebook cell. How do I do this?

This question is related to python jupyter-notebook

The answer is


A general purpose set of functions to render any python data structure (dicts and lists nested together) as HTML.

from IPython.display import HTML, display

def _render_list_html(l):
    o = []
    for e in l:
        o.append('<li>%s</li>' % _render_as_html(e))
    return '<ol>%s</ol>' % ''.join(o)

def _render_dict_html(d):
    o = []
    for k, v in d.items():
        o.append('<tr><td>%s</td><td>%s</td></tr>' % (str(k), _render_as_html(v)))
    return '<table>%s</table>' % ''.join(o)

def _render_as_html(e):
    o = []
    if isinstance(e, list):
        o.append(_render_list_html(e))
    elif isinstance(e, dict):
        o.append(_render_dict_html(e))
    else:
        o.append(str(e))
    return '<html><body>%s</body></html>' % ''.join(o)

def render_as_html(e):
    display(HTML(_render_as_html(e)))

I recently used prettytable for rendering a nice ASCII table. It's similar to the postgres CLI output.

import pandas as pd
from prettytable import PrettyTable

data = [[1,2,3],[4,5,6],[7,8,9]]
df = pd.DataFrame(data, columns=['one', 'two', 'three'])

def generate_ascii_table(df):
    x = PrettyTable()
    x.field_names = df.columns.tolist()
    for row in df.values:
        x.add_row(row)
    print(x)
    return x

generate_ascii_table(df)

Output:

+-----+-----+-------+
| one | two | three |
+-----+-----+-------+
|  1  |  2  |   3   |
|  4  |  5  |   6   |
|  7  |  8  |   9   |
+-----+-----+-------+

tabletext fit this well

import tabletext

data = [[1,2,30],
        [4,23125,6],
        [7,8,999],
        ]

print tabletext.to_text(data)

result:

+-----------------+
¦ 1 ¦     2 ¦  30 ¦
+---+-------+-----¦
¦ 4 ¦ 23125 ¦   6 ¦
+---+-------+-----¦
¦ 7 ¦     8 ¦ 999 ¦
+-----------------+

If you don't mind using a bit of html, something like this should work.

from IPython.display import HTML, display

def display_table(data):
    html = "<table>"
    for row in data:
        html += "<tr>"
        for field in row:
            html += "<td><h4>%s</h4><td>"%(field)
        html += "</tr>"
    html += "</table>"
    display(HTML(html))

And then use it like this

data = [[1,2,3],[4,5,6],[7,8,9]]
display_table(data)

enter image description here


I just discovered that tabulate has a HTML option and is rather simple to use.
Quite similar to Wayne Werner's answer:

from IPython.display import HTML, display
import tabulate
table = [["Sun",696000,1989100000],
         ["Earth",6371,5973.6],
         ["Moon",1737,73.5],
         ["Mars",3390,641.85]]
display(HTML(tabulate.tabulate(table, tablefmt='html')))

Still looking for something simple to use to create more complex table layouts like with latex syntax and formatting to merge cells and do variable substitution in a notebook:
Allow references to Python variables in Markdown cells #2958


I want to output a table where each column has the smallest possible width, where columns are padded with white space (but this can be changed) and rows are separated by newlines (but this can be changed) and where each item is formatted using str (but...).


def ftable(tbl, pad='  ', sep='\n', normalize=str):

    # normalize the content to the most useful data type
    strtbl = [[normalize(it) for it in row] for row in tbl] 

    # next, for each column we compute the maximum width needed
    w = [0 for _ in tbl[0]]
    for row in strtbl:
        for ncol, it in enumerate(row):
            w[ncol] = max(w[ncol], len(it))

    # a string is built iterating on the rows and the items of `strtbl`:
    #   items are  prepended white space to an uniform column width
    #   formatted items are `join`ed using `pad` (by default "  ")
    #   eventually we join the rows using newlines and return
    return sep.join(pad.join(' '*(wid-len(it))+it for wid, it in zip(w, row))
                                                      for row in strtbl)

The function signature, ftable(tbl, pad=' ', sep='\n', normalize=str), with its default arguments is intended to provide for maximum flexibility.

You can customize

  • the column padding,
  • the row separator, (e.g., pad='&', sep='\\\\\n' to have the bulk of a LaTeX table)
  • the function to be used to normalize the input to a common string format --- by default, for the maximum generality it is str but if you know that all your data is floating point lambda item: "%.4f"%item could be a reasonable choice, etc.

Superficial testing:

I need some test data, possibly involving columns of different width so that the algorithm needs to be a little more sophisticated (but just a little bit;)

In [1]: from random import randrange

In [2]: table = [[randrange(10**randrange(10)) for i in range(5)] for j in range(3)]

In [3]: table
Out[3]: 
[[974413992, 510, 0, 3114, 1],
 [863242961, 0, 94924, 782, 34],
 [1060993, 62, 26076, 75832, 833174]]

In [4]: print(ftable(table))
974413992  510      0   3114       1
863242961    0  94924    782      34
  1060993   62  26076  75832  833174

In [5]: print(ftable(table, pad='|'))
974413992|510|    0| 3114|     1
863242961|  0|94924|  782|    34
  1060993| 62|26076|75832|833174

Ok, so this was a bit harder than I though:

def print_matrix(list_of_list):
    number_width = len(str(max([max(i) for i in list_of_list])))
    cols = max(map(len, list_of_list))
    output = '+'+('-'*(number_width+2)+'+')*cols + '\n'
    for row in list_of_list:
        for column in row:
            output += '|' + ' {:^{width}d} '.format(column, width = number_width)
        output+='|\n+'+('-'*(number_width+2)+'+')*cols + '\n'
    return output

This should work for variable number of rows, columns and number of digits (for numbers)

data = [[1,2,30],
        [4,23125,6],
        [7,8,999],
        ]
print print_matrix(data)
>>>>+-------+-------+-------+
    |   1   |   2   |  30   |
    +-------+-------+-------+
    |   4   | 23125 |   6   |
    +-------+-------+-------+
    |   7   |   8   |  999  |
    +-------+-------+-------+

There is a nice trick: wrap the data with pandas DataFrame.

import pandas as pd
data = [[1, 2], [3, 4]]
pd.DataFrame(data, columns=["Foo", "Bar"])

It displays data like:

  | Foo | Bar |
0 | 1   | 2   |
1 | 3   | 4   |

I used to have the same problem. I could not find anything that would help me so I ended up making the class PrintTable--code below. There is also an output. The usage is simple:

ptobj = PrintTable(yourdata, column_captions, column_widths, text_aligns)
ptobj.print()

or in one line:

PrintTable(yourdata, column_captions, column_widths, text_aligns).print()

Output:

-------------------------------------------------------------------------------------------------------------
  Name                                     | Column 1   | Column 2   | Column 3   | Column 4   | Column 5    
-------------------------------------------------------------------------------------------------------------
  Very long name 0                         |          0 |          0 |          0 |          0 |          0  
  Very long name 1                         |          1 |          2 |          3 |          4 |          5  
  Very long name 2                         |          2 |          4 |          6 |          8 |         10  
  Very long name 3                         |          3 |          6 |          9 |         12 |         15  
  Very long name 4                         |          4 |          8 |         12 |         16 |         20  
  Very long name 5                         |          5 |         10 |         15 |         20 |         25  
  Very long name 6                         |          6 |         12 |         18 |         24 |         30  
  Very long name 7                         |          7 |         14 |         21 |         28 |         35  
  Very long name 8                         |          8 |         16 |         24 |         32 |         40  
  Very long name 9                         |          9 |         18 |         27 |         36 |         45  
  Very long name 10                        |         10 |         20 |         30 |         40 |         50  
  Very long name 11                        |         11 |         22 |         33 |         44 |         55  
  Very long name 12                        |         12 |         24 |         36 |         48 |         60  
  Very long name 13                        |         13 |         26 |         39 |         52 |         65  
  Very long name 14                        |         14 |         28 |         42 |         56 |         70  
  Very long name 15                        |         15 |         30 |         45 |         60 |         75  
  Very long name 16                        |         16 |         32 |         48 |         64 |         80  
  Very long name 17                        |         17 |         34 |         51 |         68 |         85  
  Very long name 18                        |         18 |         36 |         54 |         72 |         90  
  Very long name 19                        |         19 |         38 |         57 |         76 |         95  
-------------------------------------------------------------------------------------------------------------

The code for the class PrintTable

# -*- coding: utf-8 -*-

# Class
class PrintTable:
    def __init__(self, values, captions, widths, aligns):
    if not all([len(values[0]) == len(x) for x in [captions, widths, aligns]]):
        raise Exception()
    self._tablewidth = sum(widths) + 3*(len(captions)-1) + 4
    self._values = values
    self._captions = captions
    self._widths = widths
    self._aligns = aligns

    def print(self):
    self._printTable()

    def _printTable(self):
    formattext_head = ""
    formattext_cell = ""
    for i,v in enumerate(self._widths):
        formattext_head += "{" + str(i) + ":<" + str(v) + "} | "
        formattext_cell += "{" + str(i) + ":" + self._aligns[i] + str(v) + "} | "
    formattext_head = formattext_head[:-3]
    formattext_head = "  " + formattext_head.strip() + "  "
    formattext_cell = formattext_cell[:-3]
    formattext_cell = "  " + formattext_cell.strip() + "  "

    print("-"*self._tablewidth)
    print(formattext_head.format(*self._captions))
    print("-"*self._tablewidth)
    for w in self._values:
        print(formattext_cell.format(*w))
    print("-"*self._tablewidth)

Demonstration

# Demonstration

headername = ["Column {}".format(x) for x in range(6)]
headername[0] = "Name"
data = [["Very long name {}".format(x), x, x*2, x*3, x*4, x*5] for x in range(20)] 

PrintTable(data, \
       headername, \
       [70, 10, 10, 10, 10, 10], \
       ["<",">",">",">",">",">"]).print()

You could try to use the following function

def tableIt(data):
    for lin in data:
        print("+---"*len(lin)+"+")
        for inlin in lin:
            print("|",str(inlin),"", end="")
        print("|")
    print("+---"*len(lin)+"+")

data = [[1,2,3,2,3],[1,2,3,2,3],[1,2,3,2,3],[1,2,3,2,3]]

tableIt(data)