Easiest way to turn a list into an HTML table in python?

Just for future reference, I implemented a small Python module called simpletable to provide easy HTML table generation. It also that deals with the issue described in this question.

The usage is as simple as below:

import simpletable

test_data = [str(x) for x in range(20)]
formatted_data = simpletable.fit_data_to_columns(test_data, 5)
table = simpletable.SimpleTable(formatted_data)
html_page = simpletable.HTMLPage(table)
html_page.save("test_page.html")

Since it does not require third-party packages, you can just get the code from my repository and use it in your projects.

Use tabulate

from tabulate import tabulate

table = [['one','two','three'],['four','five','six'],['seven','eight','nine']]

print(tabulate(table, tablefmt='html'))

Which produces the following output.

<table>
<tbody>
<tr><td>one  </td><td>two  </td><td>three</td></tr>
<tr><td>four </td><td>five </td><td>six  </td></tr>
<tr><td>seven</td><td>eight</td><td>nine </td></tr>
</tbody>
</table>

I would decompose your problem into two parts:

• given a "flat list", produce a list of sublists where the sublists are of a given length and the overall list may be walked into either a "row major" order (your first and third example) or "column major" (your second example);
• given a list of sublists with string items, produce an HTML table out of it.

I think the two tasks are really very distinct and there's nothing to gain (and much to lose) in mushing them up, so I would be astonished if any well-designed library did such mushing.

For point 1, row-major is easy:

def row_major(alist, sublen):      
  return [alist[i:i+sublen] for i in range(0, len(alist), sublen)]

and column-major not that bad:

def col_major(alist, sublen):
  numrows = (len(alist)+sublen-1) // sublen 
  return [alist[i::sublen] for i in range(numrows)]

for example...:

L = ['one','two','three','four','five','six','seven','eight','nine']
for r in row_major(L, 3): print r
print
for r in col_major(L, 3): print r
for r in row_major(L, 4): print r

produces your three desired results (one list per row, not in HTML form yet;-).

The second half of the problem -- produce an HTML table from a list of lists of strings:

def html_table(lol):
  print '<table>'
  for sublist in lol:
    print '  <tr><td>'
    print '    </td><td>'.join(sublist)
    print '  </td></tr>'
  print '</table>'

If you want to get it as a single string rather than print it out, change each print into yield and use '\n'.join(html_table(lol)).

Now you have two simple, useful, usable and reusable building blocks -- having them separate will come in handy whenever you want to present your data as anything BUT an HTML table, and also whenever the list-of-lists to present as an HTML table comes from any other way of building it. Putting them together is easy to do in your application code, but of course it's also easy to do a simple "glue routine", e.g., assuming the yield-based version of html_table and that a single string result is desired:

def list_to_html_table(alist, sublength, column_major=False):
  if column_major:
    lol = col_major(alist, sublength)
  else:
    lol = row_major(alist, sublength)
  return ''.join(html_table(lol))

Isn't this building-blocks approach really nicer and more pleasant, as well as more productive, than programming in terms of big blobs of mushed-up glue...?-)