initial commit, functions to print table (and generate header and row ASCII strings)

tableprint.py

@@ -0,0 +1,175 @@
+"""
+Module to nicely format ASCII table rows for display
+
+"""
+
+# exports
+__all__ = ['table', 'row', 'header']
+
+
+def table(data, headers, options=None):
+    """
+    Print an ASCII table with the given data
+
+    Parameters
+    ----------
+    data : array_like
+        An (m x n) array containing the data to print (m rows of n columns)
+
+    headers : list
+        A list of n strings consisting of the header of each of the n columns
+
+    options : dict
+        A dictionary of options. Defaults:
+        {
+            'column_width'  : 10,       # the width of each column in the table
+            'outer_char'    : '|',      # the character defining the outer border of the table
+            'corner_char'   : '+',      # printed at the junctions of the table lines
+            'line_char'     : '-',      # character as part of each horizontal rule
+            'precision'     : '2f'      # precision string for formatting numbers
+        }
+
+    """
+
+    # default options
+    opts = {
+        'column_width': 10,
+        'outer_char': '|',
+        'corner_char': '+',
+        'line_char': '-',
+        'precision': '2f'
+    }
+
+    # user-specified options
+    if options:
+        opts.update(options)
+
+    # the hr line
+    hrule = hr(len(headers), column_width=opts['column_width'],
+               corner_char=opts['corner_char'], line_char=opts['line_char'])
+
+    # get the header string
+    headerstr = [hrule, header(headers, column_width=opts['column_width'], outer_char=opts['outer_char']), hrule]
+
+    # parse each row
+    tablestr = headerstr + [row(d, column_width=opts['column_width'], precision=opts['precision'],
+                           outer_char=opts['outer_char']) for d in data] + [hrule]
+
+    # print the table
+    print('\n'.join(tablestr))
+
+
+def header(headers, column_width=10, outer_char='|'):
+    """
+    Returns a formatted ASCII row of column header strings
+
+    Parameters
+    ----------
+    headers : list of strings
+        A list of n strings, the column headers
+
+    column_width : int
+        The width of each column (Default: 10)
+
+    outer_char : string
+        A character printed at the edges of each column (Default: '|')
+
+    Returns
+    -------
+    headerstr : string
+        A string consisting of the full header row to print
+
+    """
+
+    # string formatter
+    fmt = map(lambda x: '{:<' + str(column_width) + '}', headers)
+
+    # build the base string
+    basestr = (' %s ' % outer_char).join(fmt)
+
+    # build the formatted str
+    headerstr = outer_char + basestr.format(*headers) + outer_char
+
+    return headerstr
+
+
+def row(values, column_width=10, precision='2f', outer_char='|'):
+    """
+    Returns a formatted ASCII row of data
+
+    Parameters
+    ----------
+    values : array_like
+        An iterable array of data (numbers of strings), each value is printed in a separate column
+
+    column_width : int
+        The width of each column (Default: 10)
+
+    precision : string
+        The precision format string used to format numbers in the values array (Default: '2f')
+
+    outer_char : string
+        A character printed at the edges of each column (Default : '|')
+
+    Returns
+    -------
+    rowstr : string
+        A string consisting of the full row of data to print
+
+    """
+
+    # mapping function for string formatting
+    def mapdata(d):
+
+        if isinstance(d, str):
+            return ('{:>%i}' % column_width).format(d)
+
+        elif isinstance(d, (int, float)):
+            return ('{:>%i.%s}' % (column_width, precision)).format(d)
+
+        else:
+            raise ValueError('Elements in the values array must be strings, ints, or floats')
+
+    # string formatter
+    fmt = map(mapdata, values)
+
+    # build the base string
+    basestr = (' %s ' % outer_char).join(fmt)
+
+    # build the formatted string
+    rowstr = outer_char + basestr + outer_char
+
+    return rowstr
+
+
+def hr(ncols, column_width=10, corner_char='+', line_char='-', outer_char='|'):
+    """
+    Returns a formatted string used as a border between table rows
+
+    Parameters
+    ----------
+    ncols : int
+        The number of columns in the table
+
+    column_width : int
+        The width of each column (Default: 10)
+
+    corner_char : string
+        A character printed at the intersection of column edges and the row border (Default: '+')
+
+    line_char : string
+        A character printed in between column edges, defines the row border (Default: '-')
+
+    outer_char : string
+        A character printed at the left and right outer edge of the row (Default: '|')
+
+    Returns
+    -------
+    rowstr : string
+        A string consisting of the row border to print
+
+    """
+
+    hrstr = corner_char.join([('{:%s^%i}' % (line_char, column_width+2)).format('') for _ in range(ncols)])
+
+    return outer_char + hrstr[1:-1] + outer_char