Source code for astropy.io.ascii.latex

# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""An extensible ASCII table reader and writer.

latex.py:
  Classes to read and write LaTeX tables

:Copyright: Smithsonian Astrophysical Observatory (2011)
:Author: Tom Aldcroft (aldcroft@head.cfa.harvard.edu)
"""


import re

from . import core

latexdicts = {
    "AA": {
        "tabletype": "table",
        "header_start": r"\hline \hline",
        "header_end": r"\hline",
        "data_end": r"\hline",
    },
    "doublelines": {
        "tabletype": "table",
        "header_start": r"\hline \hline",
        "header_end": r"\hline\hline",
        "data_end": r"\hline\hline",
    },
    "template": {
        "tabletype": "tabletype",
        "caption": "caption",
        "tablealign": "tablealign",
        "col_align": "col_align",
        "preamble": "preamble",
        "header_start": "header_start",
        "header_end": "header_end",
        "data_start": "data_start",
        "data_end": "data_end",
        "tablefoot": "tablefoot",
        "units": {"col1": "unit of col1", "col2": "unit of col2"},
    },
}


RE_COMMENT = re.compile(r"(?<!\\)%")  # % character but not \%


def add_dictval_to_list(adict, key, alist):
    """
    Add a value from a dictionary to a list

    Parameters
    ----------
    adict : dictionary
    key : hashable
    alist : list
        List where value should be added
    """
    if key in adict:
        if isinstance(adict[key], str):
            alist.append(adict[key])
        else:
            alist.extend(adict[key])


def find_latex_line(lines, latex):
    """
    Find the first line which matches a patters

    Parameters
    ----------
    lines : list
        List of strings
    latex : str
        Search pattern

    Returns
    -------
    line_num : int, None
        Line number. Returns None, if no match was found

    """
    re_string = re.compile(latex.replace("\\", "\\\\"))
    for i, line in enumerate(lines):
        if re_string.match(line):
            return i
    else:
        return None


class LatexInputter(core.BaseInputter):
    def process_lines(self, lines):
        return [lin.strip() for lin in lines]


class LatexSplitter(core.BaseSplitter):
    """Split LaTeX table data. Default delimiter is `&`."""

    delimiter = "&"

    def __call__(self, lines):
        last_line = RE_COMMENT.split(lines[-1])[0].strip()
        if not last_line.endswith(r"\\"):
            lines[-1] = last_line + r"\\"

        return super().__call__(lines)

    def process_line(self, line):
        """Remove whitespace at the beginning or end of line. Also remove
        \\ at end of line"""
        line = RE_COMMENT.split(line)[0]
        line = line.strip()
        if line.endswith(r"\\"):
            line = line.rstrip(r"\\")
        else:
            raise core.InconsistentTableError(
                r"Lines in LaTeX table have to end with \\"
            )
        return line

    def process_val(self, val):
        """Remove whitespace and {} at the beginning or end of value."""
        val = val.strip()
        if val and (val[0] == "{") and (val[-1] == "}"):
            val = val[1:-1]
        return val

    def join(self, vals):
        """Join values together and add a few extra spaces for readability"""
        delimiter = " " + self.delimiter + " "
        return delimiter.join(x.strip() for x in vals) + r" \\"


class LatexHeader(core.BaseHeader):
    """Class to read the header of Latex Tables"""

    header_start = r"\begin{tabular}"
    splitter_class = LatexSplitter

    def start_line(self, lines):
        line = find_latex_line(lines, self.header_start)
        if line is not None:
            return line + 1
        else:
            return None

    def _get_units(self):
        units = {}
        col_units = [col.info.unit for col in self.cols]
        for name, unit in zip(self.colnames, col_units):
            if unit:
                try:
                    units[name] = unit.to_string(format="latex_inline")
                except AttributeError:
                    units[name] = unit
        return units

    def write(self, lines):
        if "col_align" not in self.latex:
            self.latex["col_align"] = len(self.cols) * "c"
        if "tablealign" in self.latex:
            align = "[" + self.latex["tablealign"] + "]"
        else:
            align = ""
        if self.latex["tabletype"] is not None:
            lines.append(r"\begin{" + self.latex["tabletype"] + r"}" + align)
        add_dictval_to_list(self.latex, "preamble", lines)
        if "caption" in self.latex:
            lines.append(r"\caption{" + self.latex["caption"] + "}")
        lines.append(self.header_start + r"{" + self.latex["col_align"] + r"}")
        add_dictval_to_list(self.latex, "header_start", lines)
        lines.append(self.splitter.join(self.colnames))
        units = self._get_units()
        if "units" in self.latex:
            units.update(self.latex["units"])
        if units:
            lines.append(
                self.splitter.join([units.get(name, " ") for name in self.colnames])
            )
        add_dictval_to_list(self.latex, "header_end", lines)


class LatexData(core.BaseData):
    """Class to read the data in LaTeX tables"""

    data_start = None
    data_end = r"\end{tabular}"
    splitter_class = LatexSplitter

    def start_line(self, lines):
        if self.data_start:
            return find_latex_line(lines, self.data_start)
        else:
            start = self.header.start_line(lines)
            if start is None:
                raise core.InconsistentTableError(r"Could not find table start")
            return start + 1

    def end_line(self, lines):
        if self.data_end:
            return find_latex_line(lines, self.data_end)
        else:
            return None

    def write(self, lines):
        add_dictval_to_list(self.latex, "data_start", lines)
        core.BaseData.write(self, lines)
        add_dictval_to_list(self.latex, "data_end", lines)
        lines.append(self.data_end)
        add_dictval_to_list(self.latex, "tablefoot", lines)
        if self.latex["tabletype"] is not None:
            lines.append(r"\end{" + self.latex["tabletype"] + "}")


[docs]class Latex(core.BaseReader): r"""LaTeX format table. This class implements some LaTeX specific commands. Its main purpose is to write out a table in a form that LaTeX can compile. It is beyond the scope of this class to implement every possible LaTeX command, instead the focus is to generate a syntactically valid LaTeX tables. This class can also read simple LaTeX tables (one line per table row, no ``\multicolumn`` or similar constructs), specifically, it can read the tables that it writes. Reading a LaTeX table, the following keywords are accepted: **ignore_latex_commands** : Lines starting with these LaTeX commands will be treated as comments (i.e. ignored). When writing a LaTeX table, the some keywords can customize the format. Care has to be taken here, because python interprets ``\\`` in a string as an escape character. In order to pass this to the output either format your strings as raw strings with the ``r`` specifier or use a double ``\\\\``. Examples:: caption = r'My table \label{mytable}' caption = 'My table \\\\label{mytable}' **latexdict** : Dictionary of extra parameters for the LaTeX output * tabletype : used for first and last line of table. The default is ``\\begin{table}``. The following would generate a table, which spans the whole page in a two-column document:: ascii.write(data, sys.stdout, Writer = ascii.Latex, latexdict = {'tabletype': 'table*'}) If ``None``, the table environment will be dropped, keeping only the ``tabular`` environment. * tablealign : positioning of table in text. The default is not to specify a position preference in the text. If, e.g. the alignment is ``ht``, then the LaTeX will be ``\\begin{table}[ht]``. * col_align : Alignment of columns If not present all columns will be centered. * caption : Table caption (string or list of strings) This will appear above the table as it is the standard in many scientific publications. If you prefer a caption below the table, just write the full LaTeX command as ``latexdict['tablefoot'] = r'\caption{My table}'`` * preamble, header_start, header_end, data_start, data_end, tablefoot: Pure LaTeX Each one can be a string or a list of strings. These strings will be inserted into the table without any further processing. See the examples below. * units : dictionary of strings Keys in this dictionary should be names of columns. If present, a line in the LaTeX table directly below the column names is added, which contains the values of the dictionary. Example:: from astropy.io import ascii data = {'name': ['bike', 'car'], 'mass': [75,1200], 'speed': [10, 130]} ascii.write(data, Writer=ascii.Latex, latexdict = {'units': {'mass': 'kg', 'speed': 'km/h'}}) If the column has no entry in the ``units`` dictionary, it defaults to the **unit** attribute of the column. If this attribute is not specified (i.e. it is None), the unit will be written as ``' '``. Run the following code to see where each element of the dictionary is inserted in the LaTeX table:: from astropy.io import ascii data = {'cola': [1,2], 'colb': [3,4]} ascii.write(data, Writer=ascii.Latex, latexdict=ascii.latex.latexdicts['template']) Some table styles are predefined in the dictionary ``ascii.latex.latexdicts``. The following generates in table in style preferred by A&A and some other journals:: ascii.write(data, Writer=ascii.Latex, latexdict=ascii.latex.latexdicts['AA']) As an example, this generates a table, which spans all columns and is centered on the page:: ascii.write(data, Writer=ascii.Latex, col_align='|lr|', latexdict={'preamble': r'\begin{center}', 'tablefoot': r'\end{center}', 'tabletype': 'table*'}) **caption** : Set table caption Shorthand for:: latexdict['caption'] = caption **col_align** : Set the column alignment. If not present this will be auto-generated for centered columns. Shorthand for:: latexdict['col_align'] = col_align """ _format_name = "latex" _io_registry_format_aliases = ["latex"] _io_registry_suffix = ".tex" _description = "LaTeX table" header_class = LatexHeader data_class = LatexData inputter_class = LatexInputter # Strictly speaking latex only supports 1-d columns so this should inherit # the base max_ndim = 1. But as reported in #11695 this causes a strange # problem with Jupyter notebook, which displays a table by first calling # _repr_latex_. For a multidimensional table this issues a stack traceback # before moving on to _repr_html_. Here we prioritize fixing the issue with # Jupyter displaying a Table with multidimensional columns. max_ndim = None def __init__( self, ignore_latex_commands=[ "hline", "vspace", "tableline", "toprule", "midrule", "bottomrule", ], latexdict={}, caption="", col_align=None, ): super().__init__() self.latex = {} # The latex dict drives the format of the table and needs to be shared # with data and header self.header.latex = self.latex self.data.latex = self.latex self.latex["tabletype"] = "table" self.latex.update(latexdict) if caption: self.latex["caption"] = caption if col_align: self.latex["col_align"] = col_align self.ignore_latex_commands = ignore_latex_commands self.header.comment = "%|" + "|".join( [r"\\" + command for command in self.ignore_latex_commands] ) self.data.comment = self.header.comment
[docs] def write(self, table=None): self.header.start_line = None self.data.start_line = None return core.BaseReader.write(self, table=table)
class AASTexHeaderSplitter(LatexSplitter): r"""Extract column names from a `deluxetable`_. This splitter expects the following LaTeX code **in a single line**: \tablehead{\colhead{col1} & ... & \colhead{coln}} """ def __call__(self, lines): return super(LatexSplitter, self).__call__(lines) def process_line(self, line): """extract column names from tablehead""" line = line.split("%")[0] line = line.replace(r"\tablehead", "") line = line.strip() if (line[0] == "{") and (line[-1] == "}"): line = line[1:-1] else: raise core.InconsistentTableError(r"\tablehead is missing {}") return line.replace(r"\colhead", "") def join(self, vals): return " & ".join([r"\colhead{" + str(x) + "}" for x in vals]) class AASTexHeader(LatexHeader): r"""In a `deluxetable <http://fits.gsfc.nasa.gov/standard30/deluxetable.sty>`_ some header keywords differ from standard LaTeX. This header is modified to take that into account. """ header_start = r"\tablehead" splitter_class = AASTexHeaderSplitter def start_line(self, lines): return find_latex_line(lines, r"\tablehead") def write(self, lines): if "col_align" not in self.latex: self.latex["col_align"] = len(self.cols) * "c" if "tablealign" in self.latex: align = "[" + self.latex["tablealign"] + "]" else: align = "" lines.append( r"\begin{" + self.latex["tabletype"] + r"}{" + self.latex["col_align"] + r"}" + align ) add_dictval_to_list(self.latex, "preamble", lines) if "caption" in self.latex: lines.append(r"\tablecaption{" + self.latex["caption"] + "}") tablehead = " & ".join([r"\colhead{" + name + "}" for name in self.colnames]) units = self._get_units() if "units" in self.latex: units.update(self.latex["units"]) if units: tablehead += r"\\ " + self.splitter.join( [units.get(name, " ") for name in self.colnames] ) lines.append(r"\tablehead{" + tablehead + "}") class AASTexData(LatexData): r"""In a `deluxetable`_ the data is enclosed in `\startdata` and `\enddata`""" data_start = r"\startdata" data_end = r"\enddata" def start_line(self, lines): return find_latex_line(lines, self.data_start) + 1 def write(self, lines): lines.append(self.data_start) lines_length_initial = len(lines) core.BaseData.write(self, lines) # To remove extra space(s) and // appended which creates an extra new line # in the end. if len(lines) > lines_length_initial: lines[-1] = re.sub(r"\s* \\ \\ \s* $", "", lines[-1], flags=re.VERBOSE) lines.append(self.data_end) add_dictval_to_list(self.latex, "tablefoot", lines) lines.append(r"\end{" + self.latex["tabletype"] + r"}")
[docs]class AASTex(Latex): """AASTeX format table. This class implements some AASTeX specific commands. AASTeX is used for the AAS (American Astronomical Society) publications like ApJ, ApJL and AJ. It derives from the ``Latex`` reader and accepts the same keywords. However, the keywords ``header_start``, ``header_end``, ``data_start`` and ``data_end`` in ``latexdict`` have no effect. """ _format_name = "aastex" _io_registry_format_aliases = ["aastex"] _io_registry_suffix = "" # AASTex inherits from Latex, so override this class attr _description = "AASTeX deluxetable used for AAS journals" header_class = AASTexHeader data_class = AASTexData def __init__(self, **kwargs): super().__init__(**kwargs) # check if tabletype was explicitly set by the user if not (("latexdict" in kwargs) and ("tabletype" in kwargs["latexdict"])): self.latex["tabletype"] = "deluxetable"