Question

The program starts as how many rows? how many coloumns? Alignment of each coloumn?(Left(L), Centre(C), Right(R)). Then accept entries(data in table) from the user. The entries should be printed in the format specified by the user? Here’s what I have done so far:

rows = input("How many rows?")
coloumns = input("How many coloumns?")
alignment = raw_input("Enter alignment of each table?")
entry = raw_input("Enter rows x cols entries:")
print entry

I think I have to format entry in such a way that it comes out exactly how the user wants. How can I do it? Thanks

Answer 1

This block of code referenced from http://ginstrom.com/scribbles/2007/09/04/pretty-printing-a-table-in-python/ will help you.

import locale
locale.setlocale(locale.LC_NUMERIC, "")
def format_num(num):
    """Format a number according to given places.
    Adds commas, etc. Will truncate floats into ints!"""

    try:
        inum = int(num)
        return locale.format("%.*f", (0, inum), True)

    except (ValueError, TypeError):
        return str(num)


def get_max_width(table, index):
    """Get the maximum width of the given column index"""
    return max([len(format_num(row[index])) for row in table])

def pprint_table(out, table):
    """Prints out a table of data, padded for alignment
    @param out: Output stream (file-like object)
    @param table: The table to print. A list of lists.
    Each row must have the same number of columns. """
    col_paddings = []

    for i in range(len(table[0])):
        col_paddings.append(get_max_width(table, i))

    for row in table:
        # left col
        print >> out, row[0].ljust(col_paddings[0] + 1),
        # rest of the cols
        for i in range(1, len(row)):
            col = format_num(row[i]).rjust(col_paddings[i] + 2)
            print >> out, col,
        print >> out


table = [["", "taste", "land speed", "life"],
    ["spam", 300101, 4, 1003],
    ["eggs", 105, 13, 42],
    ["lumberjacks", 13, 105, 10]]

import sys
out = sys.stdout
pprint_table(out, table)

In your case, because you are collecting inputs of rows, columns, alignment and entry in the table you can plug them in to construct your table variable.

• len(table[0]) is equivalent to number of columns (-1 to prevent counting in the “y-axis” labels, also known as table index).
• len(table) is
  equivalent to your number of rows (-1 to prevent counting in the table header).
• col_padding (alignment) is
  dynamically computed using rjust and ljust methods while calculating a particular column.
• And each element in your table list can be
  updated using standard python list syntax.