format.py

# pylint: disable=W0141

from itertools import izip
import sys

try:
    from StringIO import StringIO
except:
    from io import StringIO

from pandas.core.common import adjoin, isnull, notnull
from pandas.core.index import Index, MultiIndex, _ensure_index
from pandas.util import py3compat
from pandas.util.compat import OrderedDict
from pandas.util.terminal import get_terminal_size
from pandas.core.config import get_option, set_option, reset_option
import pandas.core.common as com
import pandas.lib as lib

import numpy as np

import itertools
import csv

from pandas.tseries.period import PeriodIndex

docstring_to_string = """
     Parameters
     ----------
     frame : DataFrame
         object to render
    buf : StringIO-like, optional
        buffer to write to
    columns : sequence, optional
        the subset of columns to write; default None writes all columns
    col_space : int, optional
        the minimum width of each column
    header : bool, optional
        whether to print column labels, default True
    index : bool, optional
        whether to print index (row) labels, default True
    na_rep : string, optional
        string representation of NAN to use, default 'NaN'
    formatters : list or dict of one-parameter functions, optional
        formatter functions to apply to columns' elements by position or name,
        default None, if the result is a string , it must be a unicode
        string. List must be of length equal to the number of columns.
    float_format : one-parameter function, optional
        formatter function to apply to columns' elements if they are floats
        default None
    sparsify : bool, optional
        Set to False for a DataFrame with a hierarchical index to print every
        multiindex key at each row, default True
    justify : {'left', 'right'}, default None
        Left or right-justify the column labels. If None uses the option from
        the print configuration (controlled by set_printoptions), 'right' out
        of the box.
    index_names : bool, optional
        Prints the names of the indexes, default True
    force_unicode : bool, default False
        Always return a unicode result. Deprecated in v0.10.0 as string
        formatting is now rendered to unicode by default.

    Returns
    -------
    formatted : string (or unicode, depending on data and options)"""


class SeriesFormatter(object):

    def __init__(self, series, buf=None, header=True, length=True,
                 na_rep='NaN', name=False, float_format=None, dtype=True):
        self.series = series
        self.buf = buf if buf is not None else StringIO(u"")
        self.name = name
        self.na_rep = na_rep
        self.length = length
        self.header = header

        if float_format is None:
            float_format = get_option("display.float_format")
        self.float_format = float_format
        self.dtype  = dtype

    def _get_footer(self):
        footer = u''

        if self.name:
            if getattr(self.series.index, 'freq', None):
                footer += 'Freq: %s' % self.series.index.freqstr

            if footer and self.series.name is not None:
                footer += ', '

            series_name = com.pprint_thing(self.series.name,
                                           escape_chars=('\t', '\r', '\n'))
            footer += ("Name: %s" %
                       series_name) if self.series.name is not None else ""

        if self.length:
            if footer:
                footer += ', '
            footer += 'Length: %d' % len(self.series)

        if self.dtype:
            if getattr(self.series.dtype,'name',None):
                if footer:
                    footer += ', '
                footer += 'dtype: %s' % com.pprint_thing(self.series.dtype.name)

        return unicode(footer)

    def _get_formatted_index(self):
        index = self.series.index
        is_multi = isinstance(index, MultiIndex)

        if is_multi:
            have_header = any(name for name in index.names)
            fmt_index = index.format(names=True)
        else:
            have_header = index.name is not None
            fmt_index = index.format(name=True)
        return fmt_index, have_header

    def _get_formatted_values(self):
        return format_array(self.series.values, None,
                            float_format=self.float_format,
                            na_rep=self.na_rep)

    def to_string(self):
        series = self.series

        if len(series) == 0:
            return u''

        fmt_index, have_header = self._get_formatted_index()
        fmt_values = self._get_formatted_values()

        maxlen = max(len(x) for x in fmt_index)
        pad_space = min(maxlen, 60)

        _encode_diff = _encode_diff_func()

        result = ['%s   %s'] * len(fmt_values)
        for i, (k, v) in enumerate(izip(fmt_index[1:], fmt_values)):
            try:
                idx = k.ljust(pad_space + _encode_diff(k))
            except UnicodeEncodeError:
                idx = k.ljust(pad_space)
            result[i] = result[i] % (idx, v)

        if self.header and have_header:
            result.insert(0, fmt_index[0])

        footer = self._get_footer()
        if footer:
            result.append(footer)

        return unicode(u'\n'.join(result))


def _encode_diff_func():
    if py3compat.PY3:  # pragma: no cover
        _encode_diff = lambda x: 0
    else:
        encoding = get_option("display.encoding")

        def _encode_diff(x):
            return len(x) - len(x.decode(encoding))

    return _encode_diff


def _strlen_func():
    if py3compat.PY3:  # pragma: no cover
        _strlen = len
    else:
        encoding = get_option("display.encoding")

        def _strlen(x):
            try:
                return len(x.decode(encoding))
            except UnicodeError:
                return len(x)

    return _strlen


class TableFormatter(object):

    def _get_formatter(self, i):
        if isinstance(self.formatters, (list, tuple)):
            if com.is_integer(i):
                return self.formatters[i]
            else:
                return None
        else:
            if com.is_integer(i) and i not in self.columns:
                i = self.columns[i]
            return self.formatters.get(i, None)


class DataFrameFormatter(TableFormatter):
    """
    Render a DataFrame

    self.to_string() : console-friendly tabular output
    self.to_html()   : html table
    self.to_latex()   : LaTeX tabular environment table

    """

    __doc__ = __doc__ if __doc__ else ''
    __doc__ += docstring_to_string

    def __init__(self, frame, buf=None, columns=None, col_space=None,
                 header=True, index=True, na_rep='NaN', formatters=None,
                 justify=None, float_format=None, sparsify=None,
                 index_names=True, line_width=None, **kwds):
        self.frame = frame
        self.buf = buf if buf is not None else StringIO()
        self.show_index_names = index_names

        if sparsify is None:
            sparsify = get_option("display.multi_sparse")

        self.sparsify = sparsify

        self.float_format = float_format
        self.formatters = formatters if formatters is not None else {}
        self.na_rep = na_rep
        self.col_space = col_space
        self.header = header
        self.index = index
        self.line_width = line_width

        if justify is None:
            self.justify = get_option("display.colheader_justify")
        else:
            self.justify = justify

        self.kwds = kwds

        if columns is not None:
            self.columns = _ensure_index(columns)
            self.frame = self.frame[self.columns]
        else:
            self.columns = frame.columns

    def _to_str_columns(self):
        """
        Render a DataFrame to a list of columns (as lists of strings).
        """

        # may include levels names also
        str_index = self._get_formatted_index()
        str_columns = self._get_formatted_column_labels()

        stringified = []

        _strlen = _strlen_func()

        for i, c in enumerate(self.columns):
            if self.header:
                fmt_values = self._format_col(i)
                cheader = str_columns[i]

                max_colwidth = max(self.col_space or 0,
                                   *(_strlen(x) for x in cheader))

                fmt_values = _make_fixed_width(fmt_values, self.justify,
                                               minimum=max_colwidth)

                max_len = max(np.max([_strlen(x) for x in fmt_values]),
                              max_colwidth)
                if self.justify == 'left':
                    cheader = [x.ljust(max_len) for x in cheader]
                else:
                    cheader = [x.rjust(max_len) for x in cheader]

                stringified.append(cheader + fmt_values)
            else:
                stringified = [_make_fixed_width(self._format_col(i),
                                                 self.justify)
                               for i, c in enumerate(self.columns)]

        strcols = stringified
        if self.index:
            strcols.insert(0, str_index)

        return strcols

    def to_string(self, force_unicode=None):
        """
        Render a DataFrame to a console-friendly tabular output.
        """
        import warnings
        if force_unicode is not None:  # pragma: no cover
            warnings.warn(
                "force_unicode is deprecated, it will have no effect",
                FutureWarning)

        frame = self.frame

        if len(frame.columns) == 0 or len(frame.index) == 0:
            info_line = (u'Empty %s\nColumns: %s\nIndex: %s'
                         % (type(self.frame).__name__,
                            com.pprint_thing(frame.columns),
                            com.pprint_thing(frame.index)))
            text = info_line
        else:
            strcols = self._to_str_columns()
            if self.line_width is None:
                text = adjoin(1, *strcols)
            else:
                text = self._join_multiline(*strcols)

        self.buf.writelines(text)

    def _join_multiline(self, *strcols):
        lwidth = self.line_width
        adjoin_width = 1
        strcols = list(strcols)
        if self.index:
            idx = strcols.pop(0)
            lwidth -= np.array([len(x) for x in idx]).max() + adjoin_width

        col_widths = [np.array([len(x) for x in col]).max()
                      if len(col) > 0 else 0
                      for col in strcols]
        col_bins = _binify(col_widths, lwidth)
        nbins = len(col_bins)

        str_lst = []
        st = 0
        for i, ed in enumerate(col_bins):
            row = strcols[st:ed]
            row.insert(0, idx)
            if nbins > 1:
                if ed <= len(strcols) and i < nbins - 1:
                    row.append([' \\'] + ['  '] * (len(self.frame) - 1))
                else:
                    row.append([' '] * len(self.frame))

            str_lst.append(adjoin(adjoin_width, *row))
            st = ed
        return '\n\n'.join(str_lst)

    def to_latex(self, force_unicode=None, column_format=None):
        """
        Render a DataFrame to a LaTeX tabular environment output.
        """
        def get_col_type(dtype):
            if issubclass(dtype.type, np.number):
                return 'r'
            else:
                return 'l'
        
        import warnings
        if force_unicode is not None:  # pragma: no cover
            warnings.warn(
                "force_unicode is deprecated, it will have no effect",
                FutureWarning)

        frame = self.frame

        if len(frame.columns) == 0 or len(frame.index) == 0:
            info_line = (u'Empty %s\nColumns: %s\nIndex: %s'
                         % (type(self.frame).__name__,
                            frame.columns, frame.index))
            strcols = [[info_line]]
        else:
            strcols = self._to_str_columns()
        
        if column_format is None:
            dtypes = self.frame.dtypes.values
            column_format = 'l%s' % ''.join(map(get_col_type, dtypes))
        elif not isinstance(column_format, basestring):
            raise AssertionError(('column_format must be str or unicode, not %s'
                                  % type(column_format)))

        self.buf.write('\\begin{tabular}{%s}\n' % column_format)
        self.buf.write('\\toprule\n')

        nlevels = frame.index.nlevels
        for i, row in enumerate(izip(*strcols)):
            if i == nlevels:
                self.buf.write('\\midrule\n')  # End of header
            crow = [(x.replace('_', '\\_')
                     .replace('%', '\\%')
                     .replace('&', '\\&') if x else '{}') for x in row]
            self.buf.write(' & '.join(crow))
            self.buf.write(' \\\\\n')

        self.buf.write('\\bottomrule\n')
        self.buf.write('\\end{tabular}\n')

    def _format_col(self, i):
        formatter = self._get_formatter(i)
        return format_array(self.frame.icol(i).values, formatter,
                            float_format=self.float_format,
                            na_rep=self.na_rep,
                            space=self.col_space)

    def to_html(self, classes=None):
        """
        Render a DataFrame to a html table.
        """
        html_renderer = HTMLFormatter(self, classes=classes)
        html_renderer.write_result(self.buf)

    def _get_formatted_column_labels(self):
        from pandas.core.index import _sparsify

        def is_numeric_dtype(dtype):
            return issubclass(dtype.type, np.number)

        if isinstance(self.columns, MultiIndex):
            fmt_columns = self.columns.format(sparsify=False, adjoin=False)
            fmt_columns = zip(*fmt_columns)
            dtypes = self.frame.dtypes.values
            need_leadsp = dict(zip(fmt_columns, map(is_numeric_dtype, dtypes)))
            str_columns = zip(*[[' ' + y
                                if y not in self.formatters and need_leadsp[x]
                                else y for y in x]
                                for x in fmt_columns])
            if self.sparsify:
                str_columns = _sparsify(str_columns)

            str_columns = [list(x) for x in zip(*str_columns)]
        else:
            fmt_columns = self.columns.format()
            dtypes = self.frame.dtypes
            need_leadsp = dict(zip(fmt_columns, map(is_numeric_dtype, dtypes)))
            str_columns = [[' ' + x
                            if not self._get_formatter(i) and need_leadsp[x]
                            else x]
                           for i, (col, x) in
                           enumerate(zip(self.columns, fmt_columns))]

        if self.show_index_names and self.has_index_names:
            for x in str_columns:
                x.append('')

        return str_columns

    @property
    def has_index_names(self):
        return _has_names(self.frame.index)

    @property
    def has_column_names(self):
        return _has_names(self.frame.columns)

    def _get_formatted_index(self):
        # Note: this is only used by to_string(), not by to_html().
        index = self.frame.index
        columns = self.frame.columns

        show_index_names = self.show_index_names and self.has_index_names
        show_col_names = (self.show_index_names and self.has_column_names)

        fmt = self._get_formatter('__index__')

        if isinstance(index, MultiIndex):
            fmt_index = index.format(sparsify=self.sparsify, adjoin=False,
                                     names=show_index_names,
                                     formatter=fmt)
        else:
            fmt_index = [index.format(name=show_index_names, formatter=fmt)]

        adjoined = adjoin(1, *fmt_index).split('\n')

        # empty space for columns
        if show_col_names:
            col_header = ['%s' % x for x in self._get_column_name_list()]
        else:
            col_header = [''] * columns.nlevels

        if self.header:
            return col_header + adjoined
        else:
            return adjoined

    def _get_column_name_list(self):
        names = []
        columns = self.frame.columns
        if isinstance(columns, MultiIndex):
            names.extend('' if name is None else name
                         for name in columns.names)
        else:
            names.append('' if columns.name is None else columns.name)
        return names


class HTMLFormatter(TableFormatter):

    indent_delta = 2

    def __init__(self, formatter, classes=None):
        self.fmt = formatter
        self.classes = classes

        self.frame = self.fmt.frame
        self.columns = formatter.columns
        self.elements = []
        self.bold_rows = self.fmt.kwds.get('bold_rows', False)
        self.escape = self.fmt.kwds.get('escape', True)

    def write(self, s, indent=0):
        rs = com.pprint_thing(s)
        self.elements.append(' ' * indent + rs)

    def write_th(self, s, indent=0, tags=None):
        if (self.fmt.col_space is not None
                and self.fmt.col_space > 0):
            tags = (tags or "")
            tags += 'style="min-width: %s;"' % self.fmt.col_space

        return self._write_cell(s, kind='th', indent=indent, tags=tags)

    def write_td(self, s, indent=0, tags=None):
        return self._write_cell(s, kind='td', indent=indent, tags=tags)

    def _write_cell(self, s, kind='td', indent=0, tags=None):
        if tags is not None:
            start_tag = '<%s %s>' % (kind, tags)
        else:
            start_tag = '<%s>' % kind

        if self.escape:
            # escape & first to prevent double escaping of &
            esc = OrderedDict(
                [('&', r'&amp;'), ('<', r'&lt;'), ('>', r'&gt;')]
            )
        else:
            esc = {}
        rs = com.pprint_thing(s, escape_chars=esc)
        self.write(
            '%s%s</%s>' % (start_tag, rs, kind), indent)

    def write_tr(self, line, indent=0, indent_delta=4, header=False,
                 align=None, tags=None, nindex_levels=0):
        if tags is None:
            tags = {}

        if align is None:
            self.write('<tr>', indent)
        else:
            self.write('<tr style="text-align: %s;">' % align, indent)
        indent += indent_delta

        for i, s in enumerate(line):
            val_tag = tags.get(i, None)
            if header or (self.bold_rows and i < nindex_levels):
                self.write_th(s, indent, tags=val_tag)
            else:
                self.write_td(s, indent, tags=val_tag)

        indent -= indent_delta
        self.write('</tr>', indent)

    def write_result(self, buf):
        indent = 0
        frame = self.frame

        _classes = ['dataframe']  # Default class.
        if self.classes is not None:
            if isinstance(self.classes, str):
                self.classes = self.classes.split()
            if not isinstance(self.classes, (list, tuple)):
                raise AssertionError(('classes must be list or tuple, '
                                      'not %s') % type(self.classes))
            _classes.extend(self.classes)

        self.write('<table border="1" class="%s">' % ' '.join(_classes),
                   indent)

        if len(frame.columns) == 0 or len(frame.index) == 0:
            self.write('<tbody>', indent + self.indent_delta)
            self.write_tr([repr(frame.index),
                           'Empty %s' % type(frame).__name__],
                          indent + (2 * self.indent_delta),
                          self.indent_delta)
            self.write('</tbody>', indent + self.indent_delta)
        else:
            indent += self.indent_delta
            indent = self._write_header(indent)
            indent = self._write_body(indent)

        self.write('</table>', indent)

        _put_lines(buf, self.elements)

    def _write_header(self, indent):
        if not self.fmt.header:
            # write nothing
            return indent

        def _column_header():
            if self.fmt.index:
                row = [''] * (self.frame.index.nlevels - 1)
            else:
                row = []

            if isinstance(self.columns, MultiIndex):
                if self.fmt.has_column_names and self.fmt.index:
                    row.append(single_column_table(self.columns.names))
                else:
                    row.append('')
                style = "text-align: %s;" % self.fmt.justify
                row.extend([single_column_table(c, self.fmt.justify, style) for
                            c in self.columns])
            else:
                if self.fmt.index:
                    row.append(self.columns.name or '')
                row.extend(self.columns)
            return row

        self.write('<thead>', indent)
        row = []

        indent += self.indent_delta

        if isinstance(self.columns, MultiIndex):
            template = 'colspan="%d" halign="left"'

            levels = self.columns.format(sparsify=True, adjoin=False,
                                         names=False)
            level_lengths = _get_level_lengths(levels)

            row_levels = self.frame.index.nlevels

            for lnum, (records, values) in enumerate(zip(level_lengths, levels)):
                name = self.columns.names[lnum]
                row = [''] * (row_levels - 1) + ['' if name is None
                                                 else str(name)]

                tags = {}
                j = len(row)
                for i, v in enumerate(values):
                    if i in records:
                        if records[i] > 1:
                            tags[j] = template % records[i]
                    else:
                        continue
                    j += 1
                    row.append(v)

                self.write_tr(row, indent, self.indent_delta, tags=tags,
                              header=True)
        else:
            col_row = _column_header()
            align = self.fmt.justify

            self.write_tr(col_row, indent, self.indent_delta, header=True,
                          align=align)

        if self.fmt.has_index_names:
            row = [x if x is not None else ''
                   for x in self.frame.index.names] + [''] * len(self.columns)
            self.write_tr(row, indent, self.indent_delta, header=True)

        indent -= self.indent_delta
        self.write('</thead>', indent)

        return indent

    def _write_body(self, indent):
        self.write('<tbody>', indent)
        indent += self.indent_delta

        fmt_values = {}
        for i in range(len(self.columns)):
            fmt_values[i] = self.fmt._format_col(i)

        # write values
        if self.fmt.index:
            if isinstance(self.frame.index, MultiIndex):
                self._write_hierarchical_rows(fmt_values, indent)
            else:
                self._write_regular_rows(fmt_values, indent)
        else:
            for i in range(len(self.frame)):
                row = [fmt_values[j][i] for j in range(len(self.columns))]
                self.write_tr(row, indent, self.indent_delta, tags=None)

        indent -= self.indent_delta
        self.write('</tbody>', indent)
        indent -= self.indent_delta

        return indent

    def _write_regular_rows(self, fmt_values, indent):
        ncols = len(self.columns)

        fmt = self.fmt._get_formatter('__index__')
        if fmt is not None:
            index_values = self.frame.index.map(fmt)
        else:
            index_values = self.frame.index.format()

        for i in range(len(self.frame)):
            row = []
            row.append(index_values[i])
            row.extend(fmt_values[j][i] for j in range(ncols))
            self.write_tr(row, indent, self.indent_delta, tags=None,
                          nindex_levels=1)

    def _write_hierarchical_rows(self, fmt_values, indent):
        template = 'rowspan="%d" valign="top"'

        frame = self.frame
        ncols = len(self.columns)

        idx_values = frame.index.format(sparsify=False, adjoin=False,
                                        names=False)
        idx_values = zip(*idx_values)

        if self.fmt.sparsify:
            levels = frame.index.format(sparsify=True, adjoin=False,
                                        names=False)
            level_lengths = _get_level_lengths(levels)

            for i in range(len(frame)):
                row = []
                tags = {}

                sparse_offset = 0
                j = 0
                for records, v in zip(level_lengths, idx_values[i]):
                    if i in records:
                        if records[i] > 1:
                            tags[j] = template % records[i]
                    else:
                        sparse_offset += 1
                        continue

                    j += 1
                    row.append(v)

                row.extend(fmt_values[j][i] for j in range(ncols))
                self.write_tr(row, indent, self.indent_delta, tags=tags,
                              nindex_levels=len(levels) - sparse_offset)
        else:
            for i in range(len(frame)):
                idx_values = zip(*frame.index.format(sparsify=False,
                                                     adjoin=False,
                                                     names=False))
                row = []
                row.extend(idx_values[i])
                row.extend(fmt_values[j][i] for j in range(ncols))
                self.write_tr(row, indent, self.indent_delta, tags=None,
                              nindex_levels=len(frame.index.nlevels))


def _get_level_lengths(levels):
    from itertools import groupby

    def _make_grouper():
        record = {'count': 0}

        def grouper(x):
            if x != '':
                record['count'] += 1
            return record['count']
        return grouper

    result = []
    for lev in levels:
        i = 0
        f = _make_grouper()
        recs = {}
        for key, gpr in groupby(lev, f):
            values = list(gpr)
            recs[i] = len(values)
            i += len(values)

        result.append(recs)

    return result


class CSVFormatter(object):

    def __init__(self, obj, path_or_buf, sep=",", na_rep='', float_format=None,
               cols=None, header=True, index=True, index_label=None,
               mode='w', nanRep=None, encoding=None, quoting=None,
               line_terminator='\n', chunksize=None, engine=None):

        self.engine = engine  # remove for 0.12
        self.obj = obj
        self.path_or_buf = path_or_buf
        self.sep = sep
        self.na_rep = na_rep
        self.float_format = float_format

        self.header = header
        self.index = index
        self.index_label = index_label
        self.mode = mode
        self.encoding = encoding

        if quoting is None:
            quoting = csv.QUOTE_MINIMAL
        self.quoting = quoting

        self.line_terminator = line_terminator

        if cols is None:
            cols = obj.columns

        if isinstance(cols,Index):
            cols = cols.to_native_types(na_rep=na_rep,float_format=float_format)
        else:
            cols=list(cols)
        self.cols = cols

        # preallocate data 2d list
        self.blocks = self.obj._data.blocks
        ncols = sum(len(b.items) for b in self.blocks)
        self.data =[None] * ncols

        if self.obj.columns.is_unique:
            self.colname_map = dict((k,i) for i,k in  enumerate(obj.columns))
        else:
            ks = [set(x.items) for x in self.blocks]
            u = len(reduce(lambda a,x: a.union(x),ks,set()))
            t = sum(map(len,ks))
            if u != t:
                if len(set(self.cols)) != len(self.cols):
                    raise NotImplementedError("duplicate columns with differing dtypes are unsupported")
            else:
                # if columns are not unique and we acces this,
                # we're doing it wrong
                pass


        if chunksize is None:
            chunksize = (100000/ (len(self.cols) or 1)) or 1
        self.chunksize = chunksize

        self.data_index = obj.index
        if isinstance(obj.index, PeriodIndex):
            self.data_index = obj.index.to_timestamp()

        self.nlevels = getattr(self.data_index, 'nlevels', 1)
        if not index:
            self.nlevels = 0

    # legacy to be removed in 0.12
    def _helper_csv(self, writer, na_rep=None, cols=None,
                    header=True, index=True,
                    index_label=None, float_format=None):
        if cols is None:
            cols = self.columns

        series = {}
        for k, v in self.obj._series.iteritems():
            series[k] = v.values


        has_aliases = isinstance(header, (tuple, list, np.ndarray))
        if has_aliases or header:
            if index:
                # should write something for index label
                if index_label is not False:
                    if index_label is None:
                        if isinstance(self.obj.index, MultiIndex):
                            index_label = []
                            for i, name in enumerate(self.obj.index.names):
                                if name is None:
                                    name = ''
                                index_label.append(name)
                        else:
                            index_label = self.obj.index.name
                            if index_label is None:
                                index_label = ['']
                            else:
                                index_label = [index_label]
                    elif not isinstance(index_label, (list, tuple, np.ndarray)):
                        # given a string for a DF with Index
                        index_label = [index_label]

                    encoded_labels = list(index_label)
                else:
                    encoded_labels = []

                if has_aliases:
                    if len(header) != len(cols):
                        raise ValueError(('Writing %d cols but got %d aliases'
                                          % (len(cols), len(header))))
                    else:
                        write_cols = header
                else:
                    write_cols = cols
                encoded_cols = list(write_cols)

                writer.writerow(encoded_labels + encoded_cols)
            else:
                encoded_cols = list(cols)
                writer.writerow(encoded_cols)

        data_index = self.obj.index
        if isinstance(self.obj.index, PeriodIndex):
            data_index = self.obj.index.to_timestamp()

        nlevels = getattr(data_index, 'nlevels', 1)
        for j, idx in enumerate(data_index):
            row_fields = []
            if index:
                if nlevels == 1:
                    row_fields = [idx]
                else: # handle MultiIndex
                    row_fields = list(idx)
            for i, col in enumerate(cols):
                val = series[col][j]
                if lib.checknull(val):
                    val = na_rep

                if float_format is not None and com.is_float(val):
                    val = float_format % val
                elif isinstance(val, np.datetime64):
                    val = lib.Timestamp(val)._repr_base

                row_fields.append(val)

            writer.writerow(row_fields)

    def save(self):
        # create the writer & save
        if hasattr(self.path_or_buf, 'read'):
            f = self.path_or_buf
            close = False
        else:
            f = com._get_handle(self.path_or_buf, self.mode, encoding=self.encoding)
            close = True

        try:
            if self.encoding is not None:
                self.writer = com.UnicodeWriter(f, lineterminator=self.line_terminator,
                                                delimiter=self.sep, encoding=self.encoding,
                                                quoting=self.quoting)
            else:
                self.writer = csv.writer(f, lineterminator=self.line_terminator,
                                         delimiter=self.sep, quoting=self.quoting)

            if self.engine == 'python':
            # to be removed in 0.12
                self._helper_csv(self.writer, na_rep=self.na_rep,
                                 float_format=self.float_format, cols=self.cols,
                                 header=self.header, index=self.index,
                                 index_label=self.index_label)

            else:
                self._save()


        finally:
            if close:
                f.close()

    def _save_header(self):

        writer = self.writer
        obj = self.obj
        index_label = self.index_label
        cols = self.cols
        header = self.header

        has_aliases = isinstance(header, (tuple, list, np.ndarray))
        if has_aliases or self.header:
            if self.index:
                # should write something for index label
                if index_label is not False:
                    if index_label is None:
                        if isinstance(obj.index, MultiIndex):
                            index_label = []
                            for i, name in enumerate(obj.index.names):
                                if name is None:
                                    name = ''
                                index_label.append(name)
                        else:
                            index_label = obj.index.name
                            if index_label is None:
                                index_label = ['']
                            else:
                                index_label = [index_label]
                    elif not isinstance(index_label, (list, tuple, np.ndarray)):
                        # given a string for a DF with Index
                        index_label = [index_label]

                    encoded_labels = list(index_label)
                else:
                    encoded_labels = []

                if has_aliases:
                    if len(header) != len(cols):
                        raise ValueError(('Writing %d cols but got %d aliases'
                                          % (len(cols), len(header))))
                    else:
                        write_cols = header
                else:
                    write_cols = cols
                encoded_cols = list(write_cols)

                writer.writerow(encoded_labels + encoded_cols)
            else:
                encoded_cols = list(cols)
                writer.writerow(encoded_cols)

    def _save(self):

        self._save_header()

        nrows = len(self.data_index)

        # write in chunksize bites
        chunksize = self.chunksize
        chunks = int(nrows / chunksize)+1

        for i in xrange(chunks):
            start_i = i * chunksize
            end_i = min((i + 1) * chunksize, nrows)
            if start_i >= end_i:
                break

            self._save_chunk(start_i, end_i)

    def _save_chunk(self, start_i, end_i):

        data_index  = self.data_index

        # create the data for a chunk
        slicer = slice(start_i,end_i)
        if self.obj.columns.is_unique:
            for i in range(len(self.blocks)):
                b = self.blocks[i]
                d = b.to_native_types(slicer=slicer, na_rep=self.na_rep, float_format=self.float_format)
                for j, k in enumerate(b.items):
                    # self.data is a preallocated list
                    self.data[self.colname_map[k]] = d[j]
        else:
            for i in range(len(self.cols)):
                self.data[i] = self.obj.icol(i).values[slicer].tolist()

        ix = data_index.to_native_types(slicer=slicer, na_rep=self.na_rep, float_format=self.float_format)

        lib.write_csv_rows(self.data, ix, self.nlevels, self.cols, self.writer)

# from collections import namedtuple
# ExcelCell = namedtuple("ExcelCell",
#                        'row, col, val, style, mergestart, mergeend')

class ExcelCell(object):
    __fields__ = ('row', 'col', 'val', 'style', 'mergestart', 'mergeend')
    __slots__ = __fields__

    def __init__(self, row, col, val,
                 style=None, mergestart=None, mergeend=None):
        self.row = row
        self.col = col
        self.val = val
        self.style = style
        self.mergestart = mergestart
        self.mergeend = mergeend


header_style = {"font": {"bold": True},
                "borders": {"top": "thin",
                            "right": "thin",
                            "bottom": "thin",
                            "left": "thin"},
                "alignment": {"horizontal": "center"}}


class ExcelFormatter(object):
    """
    Class for formatting a DataFrame to a list of ExcelCells,

    Parameters
    ----------
    df : dataframe
    na_rep: na representation
    float_format : string, default None
            Format string for floating point numbers
    cols : sequence, optional
        Columns to write
    header : boolean or list of string, default True
        Write out column names. If a list of string is given it is
        assumed to be aliases for the column names
    index : boolean, default True
        output row names (index)
    index_label : string or sequence, default None
            Column label for index column(s) if desired. If None is given, and
            `header` and `index` are True, then the index names are used. A
            sequence should be given if the DataFrame uses MultiIndex.
    """

    def __init__(self,
                 df,
                 na_rep='',
                 float_format=None,
                 cols=None,
                 header=True,
                 index=True,
                 index_label=None
                 ):
        self.df = df
        self.rowcounter = 0
        self.na_rep = na_rep
        self.columns = cols
        if cols is None:
            self.columns = df.columns
        self.float_format = float_format
        self.index = index
        self.index_label = index_label
        self.header = header

    def _format_value(self, val):
        if lib.checknull(val):
            val = self.na_rep
        if self.float_format is not None and com.is_float(val):
            val = float(self.float_format % val)
        return val

    def _format_header_mi(self):
        has_aliases = isinstance(self.header, (tuple, list, np.ndarray))
        if not(has_aliases or self.header):
            return

        levels = self.columns.format(sparsify=True, adjoin=False,
                                     names=False)
        # level_lenghts = _get_level_lengths(levels)
        coloffset = 1
        if isinstance(self.df.index, MultiIndex):
            coloffset = len(self.df.index[0])

        # for lnum, (records, values) in enumerate(zip(level_lenghts,
        #                                              levels)):
        #     name = self.columns.names[lnum]
        #     yield ExcelCell(lnum, coloffset, name, header_style)
        #     for i in records:
        #         if records[i] > 1:
        #             yield ExcelCell(lnum,coloffset + i + 1, values[i],
        #                     header_style, lnum, coloffset + i + records[i])
        #         else:
        # yield ExcelCell(lnum, coloffset + i + 1, values[i], header_style)

        #     self.rowcounter = lnum
        lnum = 0
        for i, values in enumerate(zip(*levels)):
            v = ".".join(map(com.pprint_thing, values))
            yield ExcelCell(lnum, coloffset + i, v, header_style)

        self.rowcounter = lnum

    def _format_header_regular(self):
        has_aliases = isinstance(self.header, (tuple, list, np.ndarray))
        if has_aliases or self.header:
            coloffset = 0
            if self.index:
                coloffset = 1
            if isinstance(self.df.index, MultiIndex):
                coloffset = len(self.df.index[0])

            colnames = self.columns
            if has_aliases:
                if len(self.header) != len(self.columns):
                    raise ValueError(('Writing %d cols but got %d aliases'
                                      % (len(self.columns), len(self.header))))
                else:
                    colnames = self.header

            for colindex, colname in enumerate(colnames):
                yield ExcelCell(self.rowcounter, colindex + coloffset, colname,
                                header_style)

    def _format_header(self):
        if isinstance(self.columns, MultiIndex):
            gen = self._format_header_mi()
        else:
            gen = self._format_header_regular()

        gen2 = ()
        if self.df.index.names:
            row = [x if x is not None else ''
                   for x in self.df.index.names] + [''] * len(self.columns)
            if reduce(lambda x, y: x and y, map(lambda x: x != '', row)):
                gen2 = (ExcelCell(self.rowcounter, colindex, val, header_style)
                        for colindex, val in enumerate(row))
                self.rowcounter += 1
        return itertools.chain(gen, gen2)

    def _format_body(self):

        if isinstance(self.df.index, MultiIndex):
            return self._format_hierarchical_rows()
        else:
            return self._format_regular_rows()

    def _format_regular_rows(self):
        has_aliases = isinstance(self.header, (tuple, list, np.ndarray))
        if has_aliases or self.header:
            self.rowcounter += 1

        coloffset = 0
        # output index and index_label?
        if self.index:
            # chek aliases
            # if list only take first as this is not a MultiIndex
            if self.index_label and isinstance(self.index_label,
                                               (list, tuple, np.ndarray)):
                index_label = self.index_label[0]
            # if string good to go
            elif self.index_label and isinstance(self.index_label, str):
                index_label = self.index_label
            else:
                index_label = self.df.index.names[0]

            if index_label and self.header is not False:
                # add to same level as column names
                # if isinstance(self.df.columns, MultiIndex):
                #     yield ExcelCell(self.rowcounter, 0,
                #                 index_label, header_style)
                #     self.rowcounter += 1
                # else:
                yield ExcelCell(self.rowcounter - 1, 0,
                                index_label, header_style)

            # write index_values
            index_values = self.df.index
            if isinstance(self.df.index, PeriodIndex):
                index_values = self.df.index.to_timestamp()

            coloffset = 1
            for idx, idxval in enumerate(index_values):
                yield ExcelCell(self.rowcounter + idx, 0, idxval, header_style)

        for colidx, colname in enumerate(self.columns):
            series = self.df[colname]
            for i, val in enumerate(series):
                yield ExcelCell(self.rowcounter + i, colidx + coloffset, val)

    def _format_hierarchical_rows(self):
        has_aliases = isinstance(self.header, (tuple, list, np.ndarray))
        if has_aliases or self.header:
            self.rowcounter += 1

        gcolidx = 0
        # output index and index_label?
        if self.index:
            index_labels = self.df.index.names
            # check for aliases
            if self.index_label and isinstance(self.index_label,
                                               (list, tuple, np.ndarray)):
                index_labels = self.index_label

            # if index labels are not empty go ahead and dump
            if (filter(lambda x: x is not None, index_labels)
                    and self.header is not False):
                # if isinstance(self.df.columns, MultiIndex):
                #     self.rowcounter += 1
                # else:
                self.rowcounter -= 1
                for cidx, name in enumerate(index_labels):
                    yield ExcelCell(self.rowcounter, cidx,
                                    name, header_style)
                self.rowcounter += 1

            for indexcolvals in zip(*self.df.index):
                for idx, indexcolval in enumerate(indexcolvals):
                    yield ExcelCell(self.rowcounter + idx, gcolidx,
                                    indexcolval, header_style)
                gcolidx += 1

        for colidx, colname in enumerate(self.columns):
            series = self.df[colname]
            for i, val in enumerate(series):
                yield ExcelCell(self.rowcounter + i, gcolidx + colidx, val)

    def get_formatted_cells(self):
        for cell in itertools.chain(self._format_header(), self._format_body()
                                    ):
            cell.val = self._format_value(cell.val)
            yield cell

#----------------------------------------------------------------------
# Array formatters


def format_array(values, formatter, float_format=None, na_rep='NaN',
                 digits=None, space=None, justify='right'):
    if com.is_float_dtype(values.dtype):
        fmt_klass = FloatArrayFormatter
    elif com.is_integer_dtype(values.dtype):
        fmt_klass = IntArrayFormatter
    elif com.is_datetime64_dtype(values.dtype):
        fmt_klass = Datetime64Formatter
    elif com.is_timedelta64_dtype(values.dtype):
        fmt_klass = Timedelta64Formatter
    else:
        fmt_klass = GenericArrayFormatter

    if space is None:
        space = get_option("display.column_space")

    if float_format is None:
        float_format = get_option("display.float_format")

    if digits is None:
        digits = get_option("display.precision")

    fmt_obj = fmt_klass(values, digits, na_rep=na_rep,
                        float_format=float_format,
                        formatter=formatter, space=space,
                        justify=justify)

    return fmt_obj.get_result()


class GenericArrayFormatter(object):

    def __init__(self, values, digits=7, formatter=None, na_rep='NaN',
                 space=12, float_format=None, justify='right'):
        self.values = values
        self.digits = digits
        self.na_rep = na_rep
        self.space = space
        self.formatter = formatter
        self.float_format = float_format
        self.justify = justify

    def get_result(self):
        fmt_values = self._format_strings()
        return _make_fixed_width(fmt_values, self.justify)

    def _format_strings(self):
        if self.float_format is None:
            float_format = get_option("display.float_format")
            if float_format is None:
                fmt_str = '%% .%dg' % get_option("display.precision")
                float_format = lambda x: fmt_str % x
        else:
            float_format = self.float_format

        formatter = (lambda x: com.pprint_thing(x, escape_chars=('\t', '\r', '\n'))) \
            if self.formatter is None else self.formatter

        def _format(x):
            if self.na_rep is not None and lib.checknull(x):
                if x is None:
                    return 'None'
                return self.na_rep
            else:
                # object dtype
                return '%s' % formatter(x)

        vals = self.values

        is_float = lib.map_infer(vals, com.is_float) & notnull(vals)
        leading_space = is_float.any()

        fmt_values = []
        for i, v in enumerate(vals):
            if not is_float[i] and leading_space:
                fmt_values.append(' %s' % _format(v))
            elif is_float[i]:
                fmt_values.append(float_format(v))
            else:
                fmt_values.append(' %s' % _format(v))

        return fmt_values


class FloatArrayFormatter(GenericArrayFormatter):
    """

    """

    def __init__(self, *args, **kwargs):
        GenericArrayFormatter.__init__(self, *args, **kwargs)

        if self.float_format is not None and self.formatter is None:
            self.formatter = self.float_format

    def _format_with(self, fmt_str):
        def _val(x, threshold):
            if notnull(x):
                if threshold is None or  abs(x) >  get_option("display.chop_threshold"):
                    return  fmt_str % x
                else:
                    if fmt_str.endswith("e"): # engineering format
                        return  "0"
                    else:
                        return  fmt_str % 0
            else:

                return self.na_rep

        threshold = get_option("display.chop_threshold")
        fmt_values = [ _val(x, threshold) for x in self.values]
        return _trim_zeros(fmt_values, self.na_rep)

    def get_result(self):
        if self.formatter is not None:
            fmt_values = [self.formatter(x) for x in self.values]
        else:
            fmt_str = '%% .%df' % (self.digits - 1)
            fmt_values = self._format_with(fmt_str)

            if len(fmt_values) > 0:
                maxlen = max(len(x) for x in fmt_values)
            else:
                maxlen = 0

            too_long = maxlen > self.digits + 5

            abs_vals = np.abs(self.values)

            # this is pretty arbitrary for now
            has_large_values = (abs_vals > 1e8).any()
            has_small_values = ((abs_vals < 10 ** (-self.digits)) &
                                (abs_vals > 0)).any()

            if too_long and has_large_values:
                fmt_str = '%% .%de' % (self.digits - 1)
                fmt_values = self._format_with(fmt_str)
            elif has_small_values:
                fmt_str = '%% .%de' % (self.digits - 1)
                fmt_values = self._format_with(fmt_str)

        return _make_fixed_width(fmt_values, self.justify)


class IntArrayFormatter(GenericArrayFormatter):

    def get_result(self):
        if self.formatter:
            formatter = self.formatter
        else:
            formatter = lambda x: '% d' % x

        fmt_values = [formatter(x) for x in self.values]

        return _make_fixed_width(fmt_values, self.justify)


class Datetime64Formatter(GenericArrayFormatter):

    def get_result(self):
        if self.formatter:
            formatter = self.formatter
        else:
            formatter = _format_datetime64

        fmt_values = [formatter(x) for x in self.values]
        return _make_fixed_width(fmt_values, self.justify)

def _format_datetime64(x, tz=None):
    if isnull(x):
        return 'NaT'

    stamp = lib.Timestamp(x, tz=tz)
    return stamp._repr_base


class Timedelta64Formatter(Datetime64Formatter):

    def get_result(self):
        if self.formatter:
            formatter = self.formatter
        else:

            formatter = _format_timedelta64

        fmt_values = [formatter(x) for x in self.values]
        return _make_fixed_width(fmt_values, self.justify)

def _format_timedelta64(x):
    if isnull(x):
        return 'NaT'

    return lib.repr_timedelta64(x)

def _make_fixed_width(strings, justify='right', minimum=None):
    if len(strings) == 0:
        return strings

    _strlen = _strlen_func()
    _encode_diff = _encode_diff_func()

    max_len = np.max([_strlen(x) for x in strings])

    if minimum is not None:
        max_len = max(minimum, max_len)

    conf_max = get_option("display.max_colwidth")
    if conf_max is not None and max_len > conf_max:
        max_len = conf_max

    if justify == 'left':
        justfunc = lambda self, x: self.ljust(x)
    else:
        justfunc = lambda self, x: self.rjust(x)

    def just(x):
        try:
            eff_len = max_len + _encode_diff(x)
        except UnicodeError:
            eff_len = max_len

        if conf_max is not None:
            if (conf_max > 3) & (_strlen(x) > max_len):
                x = x[:eff_len - 3] + '...'

        return justfunc(x, eff_len)

    return [just(x) for x in strings]


def _trim_zeros(str_floats, na_rep='NaN'):
    """
    Trims zeros and decimal points.
    """
    trimmed = str_floats

    def _cond(values):
        non_na = [x for x in values if x != na_rep]
        return (len(non_na) > 0 and all([x.endswith('0') for x in non_na]) and
                not(any([('e' in x) or ('E' in x) for x in non_na])))

    while _cond(trimmed):
        trimmed = [x[:-1] if x != na_rep else x for x in trimmed]

    # trim decimal points
    return [x[:-1] if x.endswith('.') and x != na_rep else x for x in trimmed]


def single_column_table(column, align=None, style=None):
    table = '<table'
    if align is not None:
        table += (' align="%s"' % align)
    if style is not None:
        table += (' style="%s"' % style)
    table += '><tbody>'
    for i in column:
        table += ('<tr><td>%s</td></tr>' % str(i))
    table += '</tbody></table>'
    return table


def single_row_table(row):  # pragma: no cover
    table = '<table><tbody><tr>'
    for i in row:
        table += ('<td>%s</td>' % str(i))
    table += '</tr></tbody></table>'
    return table


def _has_names(index):
    if isinstance(index, MultiIndex):
        return any([x is not None for x in index.names])
    else:
        return index.name is not None


#------------------------------------------------------------------------------
# Global formatting options


def set_printoptions(precision=None, column_space=None, max_rows=None,
                     max_columns=None, colheader_justify=None,
                     max_colwidth=None, notebook_repr_html=None,
                     date_dayfirst=None, date_yearfirst=None,
                     pprint_nest_depth=None, multi_sparse=None, encoding=None):
    """
    Alter default behavior of DataFrame.toString

    precision : int
        Floating point output precision (number of significant digits). This is
        only a suggestion
    column_space : int
        Default space for DataFrame columns, defaults to 12
    max_rows : int
    max_columns : int
        max_rows and max_columns are used in __repr__() methods to decide if
        to_string() or info() is used to render an object to a string.
        Either one, or both can be set to 0 (experimental). Pandas will figure
        out how big the terminal is and will not display more rows or/and
        columns that can fit on it.
    colheader_justify
    notebook_repr_html : boolean
        When True (default), IPython notebook will use html representation for
        pandas objects (if it is available).
    date_dayfirst : boolean
        When True, prints and parses dates with the day first, eg 20/01/2005
    date_yearfirst : boolean
        When True, prints and parses dates with the year first, eg 2005/01/20
    pprint_nest_depth : int
        Defaults to 3.
        Controls the number of nested levels to process when pretty-printing
        nested sequences.
    multi_sparse : boolean
        Default True, "sparsify" MultiIndex display (don't display repeated
        elements in outer levels within groups)
    """
    import warnings
    warnings.warn("set_printoptions is deprecated, use set_option instead",
                  FutureWarning)
    if precision is not None:
        set_option("display.precision", precision)
    if column_space is not None:
        set_option("display.column_space", column_space)
    if max_rows is not None:
        set_option("display.max_rows", max_rows)
    if max_colwidth is not None:
        set_option("display.max_colwidth", max_colwidth)
    if max_columns is not None:
        set_option("display.max_columns", max_columns)
    if colheader_justify is not None:
        set_option("display.colheader_justify", colheader_justify)
    if notebook_repr_html is not None:
        set_option("display.notebook_repr_html", notebook_repr_html)
    if date_dayfirst is not None:
        set_option("display.date_dayfirst", date_dayfirst)
    if date_yearfirst is not None:
        set_option("display.date_yearfirst", date_yearfirst)
    if pprint_nest_depth is not None:
        set_option("display.pprint_nest_depth", pprint_nest_depth)
    if multi_sparse is not None:
        set_option("display.multi_sparse", multi_sparse)
    if encoding is not None:
        set_option("display.encoding", encoding)


def reset_printoptions():
    import warnings
    warnings.warn("reset_printoptions is deprecated, use reset_option instead",
                  FutureWarning)
    reset_option("^display\.")


def detect_console_encoding():
    """
    Try to find the most capable encoding supported by the console.
    slighly modified from the way IPython handles the same issue.
    """
    import locale

    encoding = None
    try:
        encoding = sys.stdout.encoding or sys.stdin.encoding
    except AttributeError:
        pass

    if not encoding or 'ascii' in encoding.lower():  # try again for something better
        try:
            encoding = locale.getpreferredencoding()
        except Exception:
            pass

    if not encoding:  # when all else fails. this will usually be "ascii"
            encoding = sys.getdefaultencoding()

    return encoding


def get_console_size():
    """Return console size as tuple = (width, height)."""
    display_width = get_option('display.width')
    display_height = get_option('display.height')

    if com.in_interactive_session():
        terminal_width, terminal_height = get_terminal_size()
    else:
        terminal_width, terminal_height = 80, 100
    
    return (display_width or terminal_width, display_height or terminal_height)


class EngFormatter(object):
    """
    Formats float values according to engineering format.

    Based on matplotlib.ticker.EngFormatter
    """

    # The SI engineering prefixes
    ENG_PREFIXES = {
        -24: "y",
        -21: "z",
        -18: "a",
        -15: "f",
        -12: "p",
        -9: "n",
        -6: "u",
        -3: "m",
        0: "",
        3: "k",
        6: "M",
        9: "G",
        12: "T",
        15: "P",
        18: "E",
        21: "Z",
        24: "Y"
    }

    def __init__(self, accuracy=None, use_eng_prefix=False):
        self.accuracy = accuracy
        self.use_eng_prefix = use_eng_prefix

    def __call__(self, num):
        """ Formats a number in engineering notation, appending a letter
        representing the power of 1000 of the original number. Some examples:

        >>> format_eng(0)       # for self.accuracy = 0
        ' 0'

        >>> format_eng(1000000) # for self.accuracy = 1,
                                #     self.use_eng_prefix = True
        ' 1.0M'

        >>> format_eng("-1e-6") # for self.accuracy = 2
                                #     self.use_eng_prefix = False
        '-1.00E-06'

        @param num: the value to represent
        @type num: either a numeric value or a string that can be converted to
                   a numeric value (as per decimal.Decimal constructor)

        @return: engineering formatted string
        """
        import decimal
        import math
        dnum = decimal.Decimal(str(num))

        sign = 1

        if dnum < 0:  # pragma: no cover
            sign = -1
            dnum = -dnum

        if dnum != 0:
            pow10 = decimal.Decimal(int(math.floor(dnum.log10() / 3) * 3))
        else:
            pow10 = decimal.Decimal(0)

        pow10 = pow10.min(max(self.ENG_PREFIXES.keys()))
        pow10 = pow10.max(min(self.ENG_PREFIXES.keys()))
        int_pow10 = int(pow10)

        if self.use_eng_prefix:
            prefix = self.ENG_PREFIXES[int_pow10]
        else:
            if int_pow10 < 0:
                prefix = 'E-%02d' % (-int_pow10)
            else:
                prefix = 'E+%02d' % int_pow10

        mant = sign * dnum / (10 ** pow10)

        if self.accuracy is None:  # pragma: no cover
            format_str = u"% g%s"
        else:
            format_str = (u"%% .%if%%s" % self.accuracy)

        formatted = format_str % (mant, prefix)

        return formatted  # .strip()


def set_eng_float_format(precision=None, accuracy=3, use_eng_prefix=False):
    """
    Alter default behavior on how float is formatted in DataFrame.
    Format float in engineering format. By accuracy, we mean the number of
    decimal digits after the floating point.

    See also EngFormatter.
    """
    if precision is not None:  # pragma: no cover
        import warnings
        warnings.warn("'precision' parameter in set_eng_float_format is "
                      "being renamed to 'accuracy'", FutureWarning)
        accuracy = precision

    set_option("display.float_format", EngFormatter(accuracy, use_eng_prefix))
    set_option("display.column_space", max(12, accuracy + 9))


def _put_lines(buf, lines):
    if any(isinstance(x, unicode) for x in lines):
        lines = [unicode(x) for x in lines]
    buf.write('\n'.join(lines))


def _binify(cols, line_width):
    adjoin_width = 1
    bins = []
    curr_width = 0
    i_last_column = len(cols) - 1
    for i, w in enumerate(cols):
        w_adjoined = w + adjoin_width
        curr_width += w_adjoined
        if i_last_column == i:
            wrap = curr_width + 1 > line_width and i > 0
        else:
            wrap = curr_width + 2 > line_width and i > 0
        if wrap:
            bins.append(i)
            curr_width = w_adjoined

    bins.append(len(cols))
    return bins

if __name__ == '__main__':
    arr = np.array([746.03, 0.00, 5620.00, 1592.36])
    # arr = np.array([11111111.1, 1.55])
    # arr = [314200.0034, 1.4125678]
    arr = np.array([327763.3119, 345040.9076, 364460.9915, 398226.8688,
                    383800.5172, 433442.9262, 539415.0568, 568590.4108,
                    599502.4276, 620921.8593, 620898.5294, 552427.1093,
                    555221.2193, 519639.7059, 388175.7, 379199.5854,
                    614898.25, 504833.3333, 560600., 941214.2857,
                    1134250., 1219550., 855736.85, 1042615.4286,
                    722621.3043, 698167.1818, 803750.])
    fmt = FloatArrayFormatter(arr, digits=7)
    print fmt.get_result()