""" Implementation details for :mod:`.mathtext`. """ import copy from collections import namedtuple import enum import functools import logging import os import re import types import unicodedata import numpy as np from pyparsing import ( Empty, Forward, Literal, NotAny, oneOf, OneOrMore, Optional, ParseBaseException, ParseException, ParseExpression, ParseFatalException, ParserElement, ParseResults, QuotedString, Regex, StringEnd, ZeroOrMore, pyparsing_common) import matplotlib as mpl from . import _api, cbook from ._mathtext_data import ( latex_to_bakoma, stix_glyph_fixes, stix_virtual_fonts, tex2uni) from .font_manager import FontProperties, findfont, get_font from .ft2font import FT2Image, KERNING_DEFAULT ParserElement.enablePackrat() _log = logging.getLogger("matplotlib.mathtext") ############################################################################## # FONTS @_api.delete_parameter("3.6", "math") def get_unicode_index(symbol, math=False): # Publicly exported. r""" Return the integer index (from the Unicode table) of *symbol*. Parameters ---------- symbol : str A single (Unicode) character, a TeX command (e.g. r'\pi') or a Type1 symbol name (e.g. 'phi'). math : bool, default: False If True (deprecated), replace ASCII hyphen-minus by Unicode minus. """ # From UTF #25: U+2212 minus sign is the preferred # representation of the unary and binary minus sign rather than # the ASCII-derived U+002D hyphen-minus, because minus sign is # unambiguous and because it is rendered with a more desirable # length, usually longer than a hyphen. # Remove this block when the 'math' parameter is deleted. if math and symbol == '-': return 0x2212 try: # This will succeed if symbol is a single Unicode char return ord(symbol) except TypeError: pass try: # Is symbol a TeX symbol (i.e. \alpha) return tex2uni[symbol.strip("\\")] except KeyError as err: raise ValueError( "'{}' is not a valid Unicode character or TeX/Type1 symbol" .format(symbol)) from err VectorParse = namedtuple("VectorParse", "width height depth glyphs rects", module="matplotlib.mathtext") VectorParse.__doc__ = r""" The namedtuple type returned by ``MathTextParser("path").parse(...)``. This tuple contains the global metrics (*width*, *height*, *depth*), a list of *glyphs* (including their positions) and of *rect*\angles. """ RasterParse = namedtuple("RasterParse", "ox oy width height depth image", module="matplotlib.mathtext") RasterParse.__doc__ = r""" The namedtuple type returned by ``MathTextParser("agg").parse(...)``. This tuple contains the global metrics (*width*, *height*, *depth*), and a raster *image*. The offsets *ox*, *oy* are always zero. """ class Output: r""" Result of `ship`\ping a box: lists of positioned glyphs and rectangles. This class is not exposed to end users, but converted to a `VectorParse` or a `RasterParse` by `.MathTextParser.parse`. """ def __init__(self, box): self.box = box self.glyphs = [] # (ox, oy, info) self.rects = [] # (x1, y1, x2, y2) def to_vector(self): w, h, d = map( np.ceil, [self.box.width, self.box.height, self.box.depth]) gs = [(info.font, info.fontsize, info.num, ox, h - oy + info.offset) for ox, oy, info in self.glyphs] rs = [(x1, h - y2, x2 - x1, y2 - y1) for x1, y1, x2, y2 in self.rects] return VectorParse(w, h + d, d, gs, rs) def to_raster(self): # Metrics y's and mathtext y's are oriented in opposite directions, # hence the switch between ymin and ymax. xmin = min([*[ox + info.metrics.xmin for ox, oy, info in self.glyphs], *[x1 for x1, y1, x2, y2 in self.rects], 0]) - 1 ymin = min([*[oy - info.metrics.ymax for ox, oy, info in self.glyphs], *[y1 for x1, y1, x2, y2 in self.rects], 0]) - 1 xmax = max([*[ox + info.metrics.xmax for ox, oy, info in self.glyphs], *[x2 for x1, y1, x2, y2 in self.rects], 0]) + 1 ymax = max([*[oy - info.metrics.ymin for ox, oy, info in self.glyphs], *[y2 for x1, y1, x2, y2 in self.rects], 0]) + 1 w = xmax - xmin h = ymax - ymin - self.box.depth d = ymax - ymin - self.box.height image = FT2Image(np.ceil(w), np.ceil(h + max(d, 0))) # Ideally, we could just use self.glyphs and self.rects here, shifting # their coordinates by (-xmin, -ymin), but this yields slightly # different results due to floating point slop; shipping twice is the # old approach and keeps baseline images backcompat. shifted = ship(self.box, (-xmin, -ymin)) for ox, oy, info in shifted.glyphs: info.font.draw_glyph_to_bitmap( image, ox, oy - info.metrics.iceberg, info.glyph, antialiased=mpl.rcParams['text.antialiased']) for x1, y1, x2, y2 in shifted.rects: height = max(int(y2 - y1) - 1, 0) if height == 0: center = (y2 + y1) / 2 y = int(center - (height + 1) / 2) else: y = int(y1) image.draw_rect_filled(int(x1), y, np.ceil(x2), y + height) return RasterParse(0, 0, w, h + d, d, image) class Fonts: """ An abstract base class for a system of fonts to use for mathtext. The class must be able to take symbol keys and font file names and return the character metrics. It also delegates to a backend class to do the actual drawing. """ def __init__(self, default_font_prop, load_glyph_flags): """ Parameters ---------- default_font_prop : `~.font_manager.FontProperties` The default non-math font, or the base font for Unicode (generic) font rendering. load_glyph_flags : int Flags passed to the glyph loader (e.g. ``FT_Load_Glyph`` and ``FT_Load_Char`` for FreeType-based fonts). """ self.default_font_prop = default_font_prop self.load_glyph_flags = load_glyph_flags def get_kern(self, font1, fontclass1, sym1, fontsize1, font2, fontclass2, sym2, fontsize2, dpi): """ Get the kerning distance for font between *sym1* and *sym2*. See `~.Fonts.get_metrics` for a detailed description of the parameters. """ return 0. def get_metrics(self, font, font_class, sym, fontsize, dpi): r""" Parameters ---------- font : str One of the TeX font names: "tt", "it", "rm", "cal", "sf", "bf", "default", "regular", "bb", "frak", "scr". "default" and "regular" are synonyms and use the non-math font. font_class : str One of the TeX font names (as for *font*), but **not** "bb", "frak", or "scr". This is used to combine two font classes. The only supported combination currently is ``get_metrics("frak", "bf", ...)``. sym : str A symbol in raw TeX form, e.g., "1", "x", or "\sigma". fontsize : float Font size in points. dpi : float Rendering dots-per-inch. Returns ------- object The returned object has the following attributes (all floats, except *slanted*): - *advance*: The advance distance (in points) of the glyph. - *height*: The height of the glyph in points. - *width*: The width of the glyph in points. - *xmin*, *xmax*, *ymin*, *ymax*: The ink rectangle of the glyph - *iceberg*: The distance from the baseline to the top of the glyph. (This corresponds to TeX's definition of "height".) - *slanted*: Whether the glyph should be considered as "slanted" (currently used for kerning sub/superscripts). """ info = self._get_info(font, font_class, sym, fontsize, dpi) return info.metrics def render_glyph( self, output, ox, oy, font, font_class, sym, fontsize, dpi): """ At position (*ox*, *oy*), draw the glyph specified by the remaining parameters (see `get_metrics` for their detailed description). """ info = self._get_info(font, font_class, sym, fontsize, dpi) output.glyphs.append((ox, oy, info)) def render_rect_filled(self, output, x1, y1, x2, y2): """ Draw a filled rectangle from (*x1*, *y1*) to (*x2*, *y2*). """ output.rects.append((x1, y1, x2, y2)) def get_xheight(self, font, fontsize, dpi): """ Get the xheight for the given *font* and *fontsize*. """ raise NotImplementedError() def get_underline_thickness(self, font, fontsize, dpi): """ Get the line thickness that matches the given font. Used as a base unit for drawing lines such as in a fraction or radical. """ raise NotImplementedError() def get_used_characters(self): """ Get the set of characters that were used in the math expression. Used by backends that need to subset fonts so they know which glyphs to include. """ return self.used_characters def get_sized_alternatives_for_symbol(self, fontname, sym): """ Override if your font provides multiple sizes of the same symbol. Should return a list of symbols matching *sym* in various sizes. The expression renderer will select the most appropriate size for a given situation from this list. """ return [(fontname, sym)] class TruetypeFonts(Fonts): """ A generic base class for all font setups that use Truetype fonts (through FT2Font). """ def __init__(self, *args, **kwargs): super().__init__(*args, **kwargs) # Per-instance cache. self._get_info = functools.lru_cache(None)(self._get_info) self._fonts = {} filename = findfont(self.default_font_prop) default_font = get_font(filename) self._fonts['default'] = default_font self._fonts['regular'] = default_font def _get_font(self, font): if font in self.fontmap: basename = self.fontmap[font] else: basename = font cached_font = self._fonts.get(basename) if cached_font is None and os.path.exists(basename): cached_font = get_font(basename) self._fonts[basename] = cached_font self._fonts[cached_font.postscript_name] = cached_font self._fonts[cached_font.postscript_name.lower()] = cached_font return cached_font def _get_offset(self, font, glyph, fontsize, dpi): if font.postscript_name == 'Cmex10': return (glyph.height / 64 / 2) + (fontsize/3 * dpi/72) return 0. # The return value of _get_info is cached per-instance. def _get_info(self, fontname, font_class, sym, fontsize, dpi): font, num, slanted = self._get_glyph(fontname, font_class, sym) font.set_size(fontsize, dpi) glyph = font.load_char(num, flags=self.load_glyph_flags) xmin, ymin, xmax, ymax = [val/64.0 for val in glyph.bbox] offset = self._get_offset(font, glyph, fontsize, dpi) metrics = types.SimpleNamespace( advance = glyph.linearHoriAdvance/65536.0, height = glyph.height/64.0, width = glyph.width/64.0, xmin = xmin, xmax = xmax, ymin = ymin+offset, ymax = ymax+offset, # iceberg is the equivalent of TeX's "height" iceberg = glyph.horiBearingY/64.0 + offset, slanted = slanted ) return types.SimpleNamespace( font = font, fontsize = fontsize, postscript_name = font.postscript_name, metrics = metrics, num = num, glyph = glyph, offset = offset ) def get_xheight(self, fontname, fontsize, dpi): font = self._get_font(fontname) font.set_size(fontsize, dpi) pclt = font.get_sfnt_table('pclt') if pclt is None: # Some fonts don't store the xHeight, so we do a poor man's xHeight metrics = self.get_metrics( fontname, mpl.rcParams['mathtext.default'], 'x', fontsize, dpi) return metrics.iceberg xHeight = (pclt['xHeight'] / 64.0) * (fontsize / 12.0) * (dpi / 100.0) return xHeight def get_underline_thickness(self, font, fontsize, dpi): # This function used to grab underline thickness from the font # metrics, but that information is just too un-reliable, so it # is now hardcoded. return ((0.75 / 12.0) * fontsize * dpi) / 72.0 def get_kern(self, font1, fontclass1, sym1, fontsize1, font2, fontclass2, sym2, fontsize2, dpi): if font1 == font2 and fontsize1 == fontsize2: info1 = self._get_info(font1, fontclass1, sym1, fontsize1, dpi) info2 = self._get_info(font2, fontclass2, sym2, fontsize2, dpi) font = info1.font return font.get_kerning(info1.num, info2.num, KERNING_DEFAULT) / 64 return super().get_kern(font1, fontclass1, sym1, fontsize1, font2, fontclass2, sym2, fontsize2, dpi) class BakomaFonts(TruetypeFonts): """ Use the Bakoma TrueType fonts for rendering. Symbols are strewn about a number of font files, each of which has its own proprietary 8-bit encoding. """ _fontmap = { 'cal': 'cmsy10', 'rm': 'cmr10', 'tt': 'cmtt10', 'it': 'cmmi10', 'bf': 'cmb10', 'sf': 'cmss10', 'ex': 'cmex10', } def __init__(self, *args, **kwargs): self._stix_fallback = StixFonts(*args, **kwargs) super().__init__(*args, **kwargs) self.fontmap = {} for key, val in self._fontmap.items(): fullpath = findfont(val) self.fontmap[key] = fullpath self.fontmap[val] = fullpath _slanted_symbols = set(r"\int \oint".split()) def _get_glyph(self, fontname, font_class, sym): font = None if fontname in self.fontmap and sym in latex_to_bakoma: basename, num = latex_to_bakoma[sym] slanted = (basename == "cmmi10") or sym in self._slanted_symbols font = self._get_font(basename) elif len(sym) == 1: slanted = (fontname == "it") font = self._get_font(fontname) if font is not None: num = ord(sym) if font is not None and font.get_char_index(num) != 0: return font, num, slanted else: return self._stix_fallback._get_glyph(fontname, font_class, sym) # The Bakoma fonts contain many pre-sized alternatives for the # delimiters. The AutoSizedChar class will use these alternatives # and select the best (closest sized) glyph. _size_alternatives = { '(': [('rm', '('), ('ex', '\xa1'), ('ex', '\xb3'), ('ex', '\xb5'), ('ex', '\xc3')], ')': [('rm', ')'), ('ex', '\xa2'), ('ex', '\xb4'), ('ex', '\xb6'), ('ex', '\x21')], '{': [('cal', '{'), ('ex', '\xa9'), ('ex', '\x6e'), ('ex', '\xbd'), ('ex', '\x28')], '}': [('cal', '}'), ('ex', '\xaa'), ('ex', '\x6f'), ('ex', '\xbe'), ('ex', '\x29')], # The fourth size of '[' is mysteriously missing from the BaKoMa # font, so I've omitted it for both '[' and ']' '[': [('rm', '['), ('ex', '\xa3'), ('ex', '\x68'), ('ex', '\x22')], ']': [('rm', ']'), ('ex', '\xa4'), ('ex', '\x69'), ('ex', '\x23')], r'\lfloor': [('ex', '\xa5'), ('ex', '\x6a'), ('ex', '\xb9'), ('ex', '\x24')], r'\rfloor': [('ex', '\xa6'), ('ex', '\x6b'), ('ex', '\xba'), ('ex', '\x25')], r'\lceil': [('ex', '\xa7'), ('ex', '\x6c'), ('ex', '\xbb'), ('ex', '\x26')], r'\rceil': [('ex', '\xa8'), ('ex', '\x6d'), ('ex', '\xbc'), ('ex', '\x27')], r'\langle': [('ex', '\xad'), ('ex', '\x44'), ('ex', '\xbf'), ('ex', '\x2a')], r'\rangle': [('ex', '\xae'), ('ex', '\x45'), ('ex', '\xc0'), ('ex', '\x2b')], r'\__sqrt__': [('ex', '\x70'), ('ex', '\x71'), ('ex', '\x72'), ('ex', '\x73')], r'\backslash': [('ex', '\xb2'), ('ex', '\x2f'), ('ex', '\xc2'), ('ex', '\x2d')], r'/': [('rm', '/'), ('ex', '\xb1'), ('ex', '\x2e'), ('ex', '\xcb'), ('ex', '\x2c')], r'\widehat': [('rm', '\x5e'), ('ex', '\x62'), ('ex', '\x63'), ('ex', '\x64')], r'\widetilde': [('rm', '\x7e'), ('ex', '\x65'), ('ex', '\x66'), ('ex', '\x67')], r'<': [('cal', 'h'), ('ex', 'D')], r'>': [('cal', 'i'), ('ex', 'E')] } for alias, target in [(r'\leftparen', '('), (r'\rightparent', ')'), (r'\leftbrace', '{'), (r'\rightbrace', '}'), (r'\leftbracket', '['), (r'\rightbracket', ']'), (r'\{', '{'), (r'\}', '}'), (r'\[', '['), (r'\]', ']')]: _size_alternatives[alias] = _size_alternatives[target] def get_sized_alternatives_for_symbol(self, fontname, sym): return self._size_alternatives.get(sym, [(fontname, sym)]) class UnicodeFonts(TruetypeFonts): """ An abstract base class for handling Unicode fonts. While some reasonably complete Unicode fonts (such as DejaVu) may work in some situations, the only Unicode font I'm aware of with a complete set of math symbols is STIX. This class will "fallback" on the Bakoma fonts when a required symbol can not be found in the font. """ # Some glyphs are not present in the `cmr10` font, and must be brought in # from `cmsy10`. Map the Unicode indices of those glyphs to the indices at # which they are found in `cmsy10`. _cmr10_substitutions = { 0x00D7: 0x00A3, # Multiplication sign. 0x2212: 0x00A1, # Minus sign. } def __init__(self, *args, **kwargs): # This must come first so the backend's owner is set correctly fallback_rc = mpl.rcParams['mathtext.fallback'] font_cls = {'stix': StixFonts, 'stixsans': StixSansFonts, 'cm': BakomaFonts }.get(fallback_rc) self._fallback_font = font_cls(*args, **kwargs) if font_cls else None super().__init__(*args, **kwargs) self.fontmap = {} for texfont in "cal rm tt it bf sf".split(): prop = mpl.rcParams['mathtext.' + texfont] font = findfont(prop) self.fontmap[texfont] = font prop = FontProperties('cmex10') font = findfont(prop) self.fontmap['ex'] = font # include STIX sized alternatives for glyphs if fallback is STIX if isinstance(self._fallback_font, StixFonts): stixsizedaltfonts = { 0: 'STIXGeneral', 1: 'STIXSizeOneSym', 2: 'STIXSizeTwoSym', 3: 'STIXSizeThreeSym', 4: 'STIXSizeFourSym', 5: 'STIXSizeFiveSym'} for size, name in stixsizedaltfonts.items(): fullpath = findfont(name) self.fontmap[size] = fullpath self.fontmap[name] = fullpath _slanted_symbols = set(r"\int \oint".split()) def _map_virtual_font(self, fontname, font_class, uniindex): return fontname, uniindex def _get_glyph(self, fontname, font_class, sym): try: uniindex = get_unicode_index(sym) found_symbol = True except ValueError: uniindex = ord('?') found_symbol = False _log.warning("No TeX to Unicode mapping for {!a}.".format(sym)) fontname, uniindex = self._map_virtual_font( fontname, font_class, uniindex) new_fontname = fontname # Only characters in the "Letter" class should be italicized in 'it' # mode. Greek capital letters should be Roman. if found_symbol: if fontname == 'it' and uniindex < 0x10000: char = chr(uniindex) if (unicodedata.category(char)[0] != "L" or unicodedata.name(char).startswith("GREEK CAPITAL")): new_fontname = 'rm' slanted = (new_fontname == 'it') or sym in self._slanted_symbols found_symbol = False font = self._get_font(new_fontname) if font is not None: if (uniindex in self._cmr10_substitutions and font.family_name == "cmr10"): font = get_font( cbook._get_data_path("fonts/ttf/cmsy10.ttf")) uniindex = self._cmr10_substitutions[uniindex] glyphindex = font.get_char_index(uniindex) if glyphindex != 0: found_symbol = True if not found_symbol: if self._fallback_font: if (fontname in ('it', 'regular') and isinstance(self._fallback_font, StixFonts)): fontname = 'rm' g = self._fallback_font._get_glyph(fontname, font_class, sym) family = g[0].family_name if family in list(BakomaFonts._fontmap.values()): family = "Computer Modern" _log.info("Substituting symbol %s from %s", sym, family) return g else: if (fontname in ('it', 'regular') and isinstance(self, StixFonts)): return self._get_glyph('rm', font_class, sym) _log.warning("Font {!r} does not have a glyph for {!a} " "[U+{:x}], substituting with a dummy " "symbol.".format(new_fontname, sym, uniindex)) font = self._get_font('rm') uniindex = 0xA4 # currency char, for lack of anything better slanted = False return font, uniindex, slanted def get_sized_alternatives_for_symbol(self, fontname, sym): if self._fallback_font: return self._fallback_font.get_sized_alternatives_for_symbol( fontname, sym) return [(fontname, sym)] class DejaVuFonts(UnicodeFonts): def __init__(self, *args, **kwargs): # This must come first so the backend's owner is set correctly if isinstance(self, DejaVuSerifFonts): self._fallback_font = StixFonts(*args, **kwargs) else: self._fallback_font = StixSansFonts(*args, **kwargs) self.bakoma = BakomaFonts(*args, **kwargs) TruetypeFonts.__init__(self, *args, **kwargs) self.fontmap = {} # Include Stix sized alternatives for glyphs self._fontmap.update({ 1: 'STIXSizeOneSym', 2: 'STIXSizeTwoSym', 3: 'STIXSizeThreeSym', 4: 'STIXSizeFourSym', 5: 'STIXSizeFiveSym', }) for key, name in self._fontmap.items(): fullpath = findfont(name) self.fontmap[key] = fullpath self.fontmap[name] = fullpath def _get_glyph(self, fontname, font_class, sym): # Override prime symbol to use Bakoma. if sym == r'\prime': return self.bakoma._get_glyph(fontname, font_class, sym) else: # check whether the glyph is available in the display font uniindex = get_unicode_index(sym) font = self._get_font('ex') if font is not None: glyphindex = font.get_char_index(uniindex) if glyphindex != 0: return super()._get_glyph('ex', font_class, sym) # otherwise return regular glyph return super()._get_glyph(fontname, font_class, sym) class DejaVuSerifFonts(DejaVuFonts): """ A font handling class for the DejaVu Serif fonts If a glyph is not found it will fallback to Stix Serif """ _fontmap = { 'rm': 'DejaVu Serif', 'it': 'DejaVu Serif:italic', 'bf': 'DejaVu Serif:weight=bold', 'sf': 'DejaVu Sans', 'tt': 'DejaVu Sans Mono', 'ex': 'DejaVu Serif Display', 0: 'DejaVu Serif', } class DejaVuSansFonts(DejaVuFonts): """ A font handling class for the DejaVu Sans fonts If a glyph is not found it will fallback to Stix Sans """ _fontmap = { 'rm': 'DejaVu Sans', 'it': 'DejaVu Sans:italic', 'bf': 'DejaVu Sans:weight=bold', 'sf': 'DejaVu Sans', 'tt': 'DejaVu Sans Mono', 'ex': 'DejaVu Sans Display', 0: 'DejaVu Sans', } class StixFonts(UnicodeFonts): """ A font handling class for the STIX fonts. In addition to what UnicodeFonts provides, this class: - supports "virtual fonts" which are complete alpha numeric character sets with different font styles at special Unicode code points, such as "Blackboard". - handles sized alternative characters for the STIXSizeX fonts. """ _fontmap = { 'rm': 'STIXGeneral', 'it': 'STIXGeneral:italic', 'bf': 'STIXGeneral:weight=bold', 'nonunirm': 'STIXNonUnicode', 'nonuniit': 'STIXNonUnicode:italic', 'nonunibf': 'STIXNonUnicode:weight=bold', 0: 'STIXGeneral', 1: 'STIXSizeOneSym', 2: 'STIXSizeTwoSym', 3: 'STIXSizeThreeSym', 4: 'STIXSizeFourSym', 5: 'STIXSizeFiveSym', } _fallback_font = False _sans = False def __init__(self, *args, **kwargs): TruetypeFonts.__init__(self, *args, **kwargs) self.fontmap = {} for key, name in self._fontmap.items(): fullpath = findfont(name) self.fontmap[key] = fullpath self.fontmap[name] = fullpath def _map_virtual_font(self, fontname, font_class, uniindex): # Handle these "fonts" that are actually embedded in # other fonts. mapping = stix_virtual_fonts.get(fontname) if (self._sans and mapping is None and fontname not in ('regular', 'default')): mapping = stix_virtual_fonts['sf'] doing_sans_conversion = True else: doing_sans_conversion = False if mapping is not None: if isinstance(mapping, dict): try: mapping = mapping[font_class] except KeyError: mapping = mapping['rm'] # Binary search for the source glyph lo = 0 hi = len(mapping) while lo < hi: mid = (lo+hi)//2 range = mapping[mid] if uniindex < range[0]: hi = mid elif uniindex <= range[1]: break else: lo = mid + 1 if range[0] <= uniindex <= range[1]: uniindex = uniindex - range[0] + range[3] fontname = range[2] elif not doing_sans_conversion: # This will generate a dummy character uniindex = 0x1 fontname = mpl.rcParams['mathtext.default'] # Fix some incorrect glyphs. if fontname in ('rm', 'it'): uniindex = stix_glyph_fixes.get(uniindex, uniindex) # Handle private use area glyphs if fontname in ('it', 'rm', 'bf') and 0xe000 <= uniindex <= 0xf8ff: fontname = 'nonuni' + fontname return fontname, uniindex @functools.lru_cache() def get_sized_alternatives_for_symbol(self, fontname, sym): fixes = { '\\{': '{', '\\}': '}', '\\[': '[', '\\]': ']', '<': '\N{MATHEMATICAL LEFT ANGLE BRACKET}', '>': '\N{MATHEMATICAL RIGHT ANGLE BRACKET}', } sym = fixes.get(sym, sym) try: uniindex = get_unicode_index(sym) except ValueError: return [(fontname, sym)] alternatives = [(i, chr(uniindex)) for i in range(6) if self._get_font(i).get_char_index(uniindex) != 0] # The largest size of the radical symbol in STIX has incorrect # metrics that cause it to be disconnected from the stem. if sym == r'\__sqrt__': alternatives = alternatives[:-1] return alternatives class StixSansFonts(StixFonts): """ A font handling class for the STIX fonts (that uses sans-serif characters by default). """ _sans = True ############################################################################## # TeX-LIKE BOX MODEL # The following is based directly on the document 'woven' from the # TeX82 source code. This information is also available in printed # form: # # Knuth, Donald E.. 1986. Computers and Typesetting, Volume B: # TeX: The Program. Addison-Wesley Professional. # # The most relevant "chapters" are: # Data structures for boxes and their friends # Shipping pages out (ship()) # Packaging (hpack() and vpack()) # Data structures for math mode # Subroutines for math mode # Typesetting math formulas # # Many of the docstrings below refer to a numbered "node" in that # book, e.g., node123 # # Note that (as TeX) y increases downward, unlike many other parts of # matplotlib. # How much text shrinks when going to the next-smallest level. SHRINK_FACTOR = 0.7 # The number of different sizes of chars to use, beyond which they will not # get any smaller NUM_SIZE_LEVELS = 6 class FontConstantsBase: """ A set of constants that controls how certain things, such as sub- and superscripts are laid out. These are all metrics that can't be reliably retrieved from the font metrics in the font itself. """ # Percentage of x-height of additional horiz. space after sub/superscripts script_space = 0.05 # Percentage of x-height that sub/superscripts drop below the baseline subdrop = 0.4 # Percentage of x-height that superscripts are raised from the baseline sup1 = 0.7 # Percentage of x-height that subscripts drop below the baseline sub1 = 0.3 # Percentage of x-height that subscripts drop below the baseline when a # superscript is present sub2 = 0.5 # Percentage of x-height that sub/superscripts are offset relative to the # nucleus edge for non-slanted nuclei delta = 0.025 # Additional percentage of last character height above 2/3 of the # x-height that superscripts are offset relative to the subscript # for slanted nuclei delta_slanted = 0.2 # Percentage of x-height that superscripts and subscripts are offset for # integrals delta_integral = 0.1 class ComputerModernFontConstants(FontConstantsBase): script_space = 0.075 subdrop = 0.2 sup1 = 0.45 sub1 = 0.2 sub2 = 0.3 delta = 0.075 delta_slanted = 0.3 delta_integral = 0.3 class STIXFontConstants(FontConstantsBase): script_space = 0.1 sup1 = 0.8 sub2 = 0.6 delta = 0.05 delta_slanted = 0.3 delta_integral = 0.3 class STIXSansFontConstants(FontConstantsBase): script_space = 0.05 sup1 = 0.8 delta_slanted = 0.6 delta_integral = 0.3 class DejaVuSerifFontConstants(FontConstantsBase): pass class DejaVuSansFontConstants(FontConstantsBase): pass # Maps font family names to the FontConstantBase subclass to use _font_constant_mapping = { 'DejaVu Sans': DejaVuSansFontConstants, 'DejaVu Sans Mono': DejaVuSansFontConstants, 'DejaVu Serif': DejaVuSerifFontConstants, 'cmb10': ComputerModernFontConstants, 'cmex10': ComputerModernFontConstants, 'cmmi10': ComputerModernFontConstants, 'cmr10': ComputerModernFontConstants, 'cmss10': ComputerModernFontConstants, 'cmsy10': ComputerModernFontConstants, 'cmtt10': ComputerModernFontConstants, 'STIXGeneral': STIXFontConstants, 'STIXNonUnicode': STIXFontConstants, 'STIXSizeFiveSym': STIXFontConstants, 'STIXSizeFourSym': STIXFontConstants, 'STIXSizeThreeSym': STIXFontConstants, 'STIXSizeTwoSym': STIXFontConstants, 'STIXSizeOneSym': STIXFontConstants, # Map the fonts we used to ship, just for good measure 'Bitstream Vera Sans': DejaVuSansFontConstants, 'Bitstream Vera': DejaVuSansFontConstants, } def _get_font_constant_set(state): constants = _font_constant_mapping.get( state.fontset._get_font(state.font).family_name, FontConstantsBase) # STIX sans isn't really its own fonts, just different code points # in the STIX fonts, so we have to detect this one separately. if (constants is STIXFontConstants and isinstance(state.fontset, StixSansFonts)): return STIXSansFontConstants return constants class Node: """A node in the TeX box model.""" def __init__(self): self.size = 0 def __repr__(self): return type(self).__name__ def get_kerning(self, next): return 0.0 def shrink(self): """ Shrinks one level smaller. There are only three levels of sizes, after which things will no longer get smaller. """ self.size += 1 def render(self, output, x, y): """Render this node.""" class Box(Node): """A node with a physical location.""" def __init__(self, width, height, depth): super().__init__() self.width = width self.height = height self.depth = depth def shrink(self): super().shrink() if self.size < NUM_SIZE_LEVELS: self.width *= SHRINK_FACTOR self.height *= SHRINK_FACTOR self.depth *= SHRINK_FACTOR def render(self, output, x1, y1, x2, y2): pass class Vbox(Box): """A box with only height (zero width).""" def __init__(self, height, depth): super().__init__(0., height, depth) class Hbox(Box): """A box with only width (zero height and depth).""" def __init__(self, width): super().__init__(width, 0., 0.) class Char(Node): """ A single character. Unlike TeX, the font information and metrics are stored with each `Char` to make it easier to lookup the font metrics when needed. Note that TeX boxes have a width, height, and depth, unlike Type1 and TrueType which use a full bounding box and an advance in the x-direction. The metrics must be converted to the TeX model, and the advance (if different from width) must be converted into a `Kern` node when the `Char` is added to its parent `Hlist`. """ def __init__(self, c, state): super().__init__() self.c = c self.fontset = state.fontset self.font = state.font self.font_class = state.font_class self.fontsize = state.fontsize self.dpi = state.dpi # The real width, height and depth will be set during the # pack phase, after we know the real fontsize self._update_metrics() def __repr__(self): return '`%s`' % self.c def _update_metrics(self): metrics = self._metrics = self.fontset.get_metrics( self.font, self.font_class, self.c, self.fontsize, self.dpi) if self.c == ' ': self.width = metrics.advance else: self.width = metrics.width self.height = metrics.iceberg self.depth = -(metrics.iceberg - metrics.height) def is_slanted(self): return self._metrics.slanted def get_kerning(self, next): """ Return the amount of kerning between this and the given character. This method is called when characters are strung together into `Hlist` to create `Kern` nodes. """ advance = self._metrics.advance - self.width kern = 0. if isinstance(next, Char): kern = self.fontset.get_kern( self.font, self.font_class, self.c, self.fontsize, next.font, next.font_class, next.c, next.fontsize, self.dpi) return advance + kern def render(self, output, x, y): self.fontset.render_glyph( output, x, y, self.font, self.font_class, self.c, self.fontsize, self.dpi) def shrink(self): super().shrink() if self.size < NUM_SIZE_LEVELS: self.fontsize *= SHRINK_FACTOR self.width *= SHRINK_FACTOR self.height *= SHRINK_FACTOR self.depth *= SHRINK_FACTOR class Accent(Char): """ The font metrics need to be dealt with differently for accents, since they are already offset correctly from the baseline in TrueType fonts. """ def _update_metrics(self): metrics = self._metrics = self.fontset.get_metrics( self.font, self.font_class, self.c, self.fontsize, self.dpi) self.width = metrics.xmax - metrics.xmin self.height = metrics.ymax - metrics.ymin self.depth = 0 def shrink(self): super().shrink() self._update_metrics() def render(self, output, x, y): self.fontset.render_glyph( output, x - self._metrics.xmin, y + self._metrics.ymin, self.font, self.font_class, self.c, self.fontsize, self.dpi) class List(Box): """A list of nodes (either horizontal or vertical).""" def __init__(self, elements): super().__init__(0., 0., 0.) self.shift_amount = 0. # An arbitrary offset self.children = elements # The child nodes of this list # The following parameters are set in the vpack and hpack functions self.glue_set = 0. # The glue setting of this list self.glue_sign = 0 # 0: normal, -1: shrinking, 1: stretching self.glue_order = 0 # The order of infinity (0 - 3) for the glue def __repr__(self): return '%s[%s]' % ( super().__repr__(), self.width, self.height, self.depth, self.shift_amount, ', '.join([repr(x) for x in self.children])) def _set_glue(self, x, sign, totals, error_type): self.glue_order = o = next( # Highest order of glue used by the members of this list. (i for i in range(len(totals))[::-1] if totals[i] != 0), 0) self.glue_sign = sign if totals[o] != 0.: self.glue_set = x / totals[o] else: self.glue_sign = 0 self.glue_ratio = 0. if o == 0: if len(self.children): _log.warning("%s %s: %r", error_type, type(self).__name__, self) def shrink(self): for child in self.children: child.shrink() super().shrink() if self.size < NUM_SIZE_LEVELS: self.shift_amount *= SHRINK_FACTOR self.glue_set *= SHRINK_FACTOR class Hlist(List): """A horizontal list of boxes.""" def __init__(self, elements, w=0., m='additional', do_kern=True): super().__init__(elements) if do_kern: self.kern() self.hpack(w=w, m=m) def kern(self): """ Insert `Kern` nodes between `Char` nodes to set kerning. The `Char` nodes themselves determine the amount of kerning they need (in `~Char.get_kerning`), and this function just creates the correct linked list. """ new_children = [] num_children = len(self.children) if num_children: for i in range(num_children): elem = self.children[i] if i < num_children - 1: next = self.children[i + 1] else: next = None new_children.append(elem) kerning_distance = elem.get_kerning(next) if kerning_distance != 0.: kern = Kern(kerning_distance) new_children.append(kern) self.children = new_children # This is a failed experiment to fake cross-font kerning. # def get_kerning(self, next): # if len(self.children) >= 2 and isinstance(self.children[-2], Char): # if isinstance(next, Char): # print "CASE A" # return self.children[-2].get_kerning(next) # elif (isinstance(next, Hlist) and len(next.children) # and isinstance(next.children[0], Char)): # print "CASE B" # result = self.children[-2].get_kerning(next.children[0]) # print result # return result # return 0.0 def hpack(self, w=0., m='additional'): r""" Compute the dimensions of the resulting boxes, and adjust the glue if one of those dimensions is pre-specified. The computed sizes normally enclose all of the material inside the new box; but some items may stick out if negative glue is used, if the box is overfull, or if a ``\vbox`` includes other boxes that have been shifted left. Parameters ---------- w : float, default: 0 A width. m : {'exactly', 'additional'}, default: 'additional' Whether to produce a box whose width is 'exactly' *w*; or a box with the natural width of the contents, plus *w* ('additional'). Notes ----- The defaults produce a box with the natural width of the contents. """ # I don't know why these get reset in TeX. Shift_amount is pretty # much useless if we do. # self.shift_amount = 0. h = 0. d = 0. x = 0. total_stretch = [0.] * 4 total_shrink = [0.] * 4 for p in self.children: if isinstance(p, Char): x += p.width h = max(h, p.height) d = max(d, p.depth) elif isinstance(p, Box): x += p.width if not np.isinf(p.height) and not np.isinf(p.depth): s = getattr(p, 'shift_amount', 0.) h = max(h, p.height - s) d = max(d, p.depth + s) elif isinstance(p, Glue): glue_spec = p.glue_spec x += glue_spec.width total_stretch[glue_spec.stretch_order] += glue_spec.stretch total_shrink[glue_spec.shrink_order] += glue_spec.shrink elif isinstance(p, Kern): x += p.width self.height = h self.depth = d if m == 'additional': w += x self.width = w x = w - x if x == 0.: self.glue_sign = 0 self.glue_order = 0 self.glue_ratio = 0. return if x > 0.: self._set_glue(x, 1, total_stretch, "Overful") else: self._set_glue(x, -1, total_shrink, "Underful") class Vlist(List): """A vertical list of boxes.""" def __init__(self, elements, h=0., m='additional'): super().__init__(elements) self.vpack(h=h, m=m) def vpack(self, h=0., m='additional', l=np.inf): """ Compute the dimensions of the resulting boxes, and to adjust the glue if one of those dimensions is pre-specified. Parameters ---------- h : float, default: 0 A height. m : {'exactly', 'additional'}, default: 'additional' Whether to produce a box whose height is 'exactly' *h*; or a box with the natural height of the contents, plus *h* ('additional'). l : float, default: np.inf The maximum height. Notes ----- The defaults produce a box with the natural height of the contents. """ # I don't know why these get reset in TeX. Shift_amount is pretty # much useless if we do. # self.shift_amount = 0. w = 0. d = 0. x = 0. total_stretch = [0.] * 4 total_shrink = [0.] * 4 for p in self.children: if isinstance(p, Box): x += d + p.height d = p.depth if not np.isinf(p.width): s = getattr(p, 'shift_amount', 0.) w = max(w, p.width + s) elif isinstance(p, Glue): x += d d = 0. glue_spec = p.glue_spec x += glue_spec.width total_stretch[glue_spec.stretch_order] += glue_spec.stretch total_shrink[glue_spec.shrink_order] += glue_spec.shrink elif isinstance(p, Kern): x += d + p.width d = 0. elif isinstance(p, Char): raise RuntimeError( "Internal mathtext error: Char node found in Vlist") self.width = w if d > l: x += d - l self.depth = l else: self.depth = d if m == 'additional': h += x self.height = h x = h - x if x == 0: self.glue_sign = 0 self.glue_order = 0 self.glue_ratio = 0. return if x > 0.: self._set_glue(x, 1, total_stretch, "Overful") else: self._set_glue(x, -1, total_shrink, "Underful") class Rule(Box): """ A solid black rectangle. It has *width*, *depth*, and *height* fields just as in an `Hlist`. However, if any of these dimensions is inf, the actual value will be determined by running the rule up to the boundary of the innermost enclosing box. This is called a "running dimension". The width is never running in an `Hlist`; the height and depth are never running in a `Vlist`. """ def __init__(self, width, height, depth, state): super().__init__(width, height, depth) self.fontset = state.fontset def render(self, output, x, y, w, h): self.fontset.render_rect_filled(output, x, y, x + w, y + h) class Hrule(Rule): """Convenience class to create a horizontal rule.""" def __init__(self, state, thickness=None): if thickness is None: thickness = state.get_current_underline_thickness() height = depth = thickness * 0.5 super().__init__(np.inf, height, depth, state) class Vrule(Rule): """Convenience class to create a vertical rule.""" def __init__(self, state): thickness = state.get_current_underline_thickness() super().__init__(thickness, np.inf, np.inf, state) _GlueSpec = namedtuple( "_GlueSpec", "width stretch stretch_order shrink shrink_order") _GlueSpec._named = { 'fil': _GlueSpec(0., 1., 1, 0., 0), 'fill': _GlueSpec(0., 1., 2, 0., 0), 'filll': _GlueSpec(0., 1., 3, 0., 0), 'neg_fil': _GlueSpec(0., 0., 0, 1., 1), 'neg_fill': _GlueSpec(0., 0., 0, 1., 2), 'neg_filll': _GlueSpec(0., 0., 0, 1., 3), 'empty': _GlueSpec(0., 0., 0, 0., 0), 'ss': _GlueSpec(0., 1., 1, -1., 1), } class Glue(Node): """ Most of the information in this object is stored in the underlying ``_GlueSpec`` class, which is shared between multiple glue objects. (This is a memory optimization which probably doesn't matter anymore, but it's easier to stick to what TeX does.) """ def __init__(self, glue_type): super().__init__() if isinstance(glue_type, str): glue_spec = _GlueSpec._named[glue_type] elif isinstance(glue_type, _GlueSpec): glue_spec = glue_type else: raise ValueError("glue_type must be a glue spec name or instance") self.glue_spec = glue_spec def shrink(self): super().shrink() if self.size < NUM_SIZE_LEVELS: g = self.glue_spec self.glue_spec = g._replace(width=g.width * SHRINK_FACTOR) class HCentered(Hlist): """ A convenience class to create an `Hlist` whose contents are centered within its enclosing box. """ def __init__(self, elements): super().__init__([Glue('ss'), *elements, Glue('ss')], do_kern=False) class VCentered(Vlist): """ A convenience class to create a `Vlist` whose contents are centered within its enclosing box. """ def __init__(self, elements): super().__init__([Glue('ss'), *elements, Glue('ss')]) class Kern(Node): """ A `Kern` node has a width field to specify a (normally negative) amount of spacing. This spacing correction appears in horizontal lists between letters like A and V when the font designer said that it looks better to move them closer together or further apart. A kern node can also appear in a vertical list, when its *width* denotes additional spacing in the vertical direction. """ height = 0 depth = 0 def __init__(self, width): super().__init__() self.width = width def __repr__(self): return "k%.02f" % self.width def shrink(self): super().shrink() if self.size < NUM_SIZE_LEVELS: self.width *= SHRINK_FACTOR class AutoHeightChar(Hlist): """ A character as close to the given height and depth as possible. When using a font with multiple height versions of some characters (such as the BaKoMa fonts), the correct glyph will be selected, otherwise this will always just return a scaled version of the glyph. """ def __init__(self, c, height, depth, state, always=False, factor=None): alternatives = state.fontset.get_sized_alternatives_for_symbol( state.font, c) xHeight = state.fontset.get_xheight( state.font, state.fontsize, state.dpi) state = state.copy() target_total = height + depth for fontname, sym in alternatives: state.font = fontname char = Char(sym, state) # Ensure that size 0 is chosen when the text is regular sized but # with descender glyphs by subtracting 0.2 * xHeight if char.height + char.depth >= target_total - 0.2 * xHeight: break shift = 0 if state.font != 0 or len(alternatives) == 1: if factor is None: factor = target_total / (char.height + char.depth) state.fontsize *= factor char = Char(sym, state) shift = (depth - char.depth) super().__init__([char]) self.shift_amount = shift class AutoWidthChar(Hlist): """ A character as close to the given width as possible. When using a font with multiple width versions of some characters (such as the BaKoMa fonts), the correct glyph will be selected, otherwise this will always just return a scaled version of the glyph. """ def __init__(self, c, width, state, always=False, char_class=Char): alternatives = state.fontset.get_sized_alternatives_for_symbol( state.font, c) state = state.copy() for fontname, sym in alternatives: state.font = fontname char = char_class(sym, state) if char.width >= width: break factor = width / char.width state.fontsize *= factor char = char_class(sym, state) super().__init__([char]) self.width = char.width def ship(box, xy=(0, 0)): """ Ship out *box* at offset *xy*, converting it to an `Output`. Since boxes can be inside of boxes inside of boxes, the main work of `ship` is done by two mutually recursive routines, `hlist_out` and `vlist_out`, which traverse the `Hlist` nodes and `Vlist` nodes inside of horizontal and vertical boxes. The global variables used in TeX to store state as it processes have become local variables here. """ ox, oy = xy cur_v = 0. cur_h = 0. off_h = ox off_v = oy + box.height output = Output(box) def clamp(value): return -1e9 if value < -1e9 else +1e9 if value > +1e9 else value def hlist_out(box): nonlocal cur_v, cur_h, off_h, off_v cur_g = 0 cur_glue = 0. glue_order = box.glue_order glue_sign = box.glue_sign base_line = cur_v left_edge = cur_h for p in box.children: if isinstance(p, Char): p.render(output, cur_h + off_h, cur_v + off_v) cur_h += p.width elif isinstance(p, Kern): cur_h += p.width elif isinstance(p, List): # node623 if len(p.children) == 0: cur_h += p.width else: edge = cur_h cur_v = base_line + p.shift_amount if isinstance(p, Hlist): hlist_out(p) else: # p.vpack(box.height + box.depth, 'exactly') vlist_out(p) cur_h = edge + p.width cur_v = base_line elif isinstance(p, Box): # node624 rule_height = p.height rule_depth = p.depth rule_width = p.width if np.isinf(rule_height): rule_height = box.height if np.isinf(rule_depth): rule_depth = box.depth if rule_height > 0 and rule_width > 0: cur_v = base_line + rule_depth p.render(output, cur_h + off_h, cur_v + off_v, rule_width, rule_height) cur_v = base_line cur_h += rule_width elif isinstance(p, Glue): # node625 glue_spec = p.glue_spec rule_width = glue_spec.width - cur_g if glue_sign != 0: # normal if glue_sign == 1: # stretching if glue_spec.stretch_order == glue_order: cur_glue += glue_spec.stretch cur_g = round(clamp(box.glue_set * cur_glue)) elif glue_spec.shrink_order == glue_order: cur_glue += glue_spec.shrink cur_g = round(clamp(box.glue_set * cur_glue)) rule_width += cur_g cur_h += rule_width def vlist_out(box): nonlocal cur_v, cur_h, off_h, off_v cur_g = 0 cur_glue = 0. glue_order = box.glue_order glue_sign = box.glue_sign left_edge = cur_h cur_v -= box.height top_edge = cur_v for p in box.children: if isinstance(p, Kern): cur_v += p.width elif isinstance(p, List): if len(p.children) == 0: cur_v += p.height + p.depth else: cur_v += p.height cur_h = left_edge + p.shift_amount save_v = cur_v p.width = box.width if isinstance(p, Hlist): hlist_out(p) else: vlist_out(p) cur_v = save_v + p.depth cur_h = left_edge elif isinstance(p, Box): rule_height = p.height rule_depth = p.depth rule_width = p.width if np.isinf(rule_width): rule_width = box.width rule_height += rule_depth if rule_height > 0 and rule_depth > 0: cur_v += rule_height p.render(output, cur_h + off_h, cur_v + off_v, rule_width, rule_height) elif isinstance(p, Glue): glue_spec = p.glue_spec rule_height = glue_spec.width - cur_g if glue_sign != 0: # normal if glue_sign == 1: # stretching if glue_spec.stretch_order == glue_order: cur_glue += glue_spec.stretch cur_g = round(clamp(box.glue_set * cur_glue)) elif glue_spec.shrink_order == glue_order: # shrinking cur_glue += glue_spec.shrink cur_g = round(clamp(box.glue_set * cur_glue)) rule_height += cur_g cur_v += rule_height elif isinstance(p, Char): raise RuntimeError( "Internal mathtext error: Char node found in vlist") hlist_out(box) return output ############################################################################## # PARSER def Error(msg): """Helper class to raise parser errors.""" def raise_error(s, loc, toks): raise ParseFatalException(s, loc, msg) return Empty().setParseAction(raise_error) class ParserState: """ Parser state. States are pushed and popped from a stack as necessary, and the "current" state is always at the top of the stack. Upon entering and leaving a group { } or math/non-math, the stack is pushed and popped accordingly. """ def __init__(self, fontset, font, font_class, fontsize, dpi): self.fontset = fontset self._font = font self.font_class = font_class self.fontsize = fontsize self.dpi = dpi def copy(self): return copy.copy(self) @property def font(self): return self._font @font.setter def font(self, name): if name in ('rm', 'it', 'bf'): self.font_class = name self._font = name def get_current_underline_thickness(self): """Return the underline thickness for this state.""" return self.fontset.get_underline_thickness( self.font, self.fontsize, self.dpi) def cmd(expr, args): r""" Helper to define TeX commands. ``cmd("\cmd", args)`` is equivalent to ``"\cmd" - (args | Error("Expected \cmd{arg}{...}"))`` where the names in the error message are taken from element names in *args*. If *expr* already includes arguments (e.g. "\cmd{arg}{...}"), then they are stripped when constructing the parse element, but kept (and *expr* is used as is) in the error message. """ def names(elt): if isinstance(elt, ParseExpression): for expr in elt.exprs: yield from names(expr) elif elt.resultsName: yield elt.resultsName csname = expr.split("{", 1)[0] err = (csname + "".join("{%s}" % name for name in names(args)) if expr == csname else expr) return csname - (args | Error(f"Expected {err}")) class Parser: """ A pyparsing-based parser for strings containing math expressions. Raw text may also appear outside of pairs of ``$``. The grammar is based directly on that in TeX, though it cuts a few corners. """ class _MathStyle(enum.Enum): DISPLAYSTYLE = 0 TEXTSTYLE = 1 SCRIPTSTYLE = 2 SCRIPTSCRIPTSTYLE = 3 _binary_operators = set( '+ * - \N{MINUS SIGN}' r''' \pm \sqcap \rhd \mp \sqcup \unlhd \times \vee \unrhd \div \wedge \oplus \ast \setminus \ominus \star \wr \otimes \circ \diamond \oslash \bullet \bigtriangleup \odot \cdot \bigtriangledown \bigcirc \cap \triangleleft \dagger \cup \triangleright \ddagger \uplus \lhd \amalg \dotplus \dotminus'''.split()) _relation_symbols = set(r''' = < > : \leq \geq \equiv \models \prec \succ \sim \perp \preceq \succeq \simeq \mid \ll \gg \asymp \parallel \subset \supset \approx \bowtie \subseteq \supseteq \cong \Join \sqsubset \sqsupset \neq \smile \sqsubseteq \sqsupseteq \doteq \frown \in \ni \propto \vdash \dashv \dots \doteqdot'''.split()) _arrow_symbols = set(r''' \leftarrow \longleftarrow \uparrow \Leftarrow \Longleftarrow \Uparrow \rightarrow \longrightarrow \downarrow \Rightarrow \Longrightarrow \Downarrow \leftrightarrow \longleftrightarrow \updownarrow \Leftrightarrow \Longleftrightarrow \Updownarrow \mapsto \longmapsto \nearrow \hookleftarrow \hookrightarrow \searrow \leftharpoonup \rightharpoonup \swarrow \leftharpoondown \rightharpoondown \nwarrow \rightleftharpoons \leadsto'''.split()) _spaced_symbols = _binary_operators | _relation_symbols | _arrow_symbols _punctuation_symbols = set(r', ; . ! \ldotp \cdotp'.split()) _overunder_symbols = set(r''' \sum \prod \coprod \bigcap \bigcup \bigsqcup \bigvee \bigwedge \bigodot \bigotimes \bigoplus \biguplus '''.split()) _overunder_functions = set("lim liminf limsup sup max min".split()) _dropsub_symbols = set(r'''\int \oint'''.split()) _fontnames = set("rm cal it tt sf bf default bb frak scr regular".split()) _function_names = set(""" arccos csc ker min arcsin deg lg Pr arctan det lim sec arg dim liminf sin cos exp limsup sinh cosh gcd ln sup cot hom log tan coth inf max tanh""".split()) _ambi_delims = set(r""" | \| / \backslash \uparrow \downarrow \updownarrow \Uparrow \Downarrow \Updownarrow . \vert \Vert""".split()) _left_delims = set(r"( [ \{ < \lfloor \langle \lceil".split()) _right_delims = set(r") ] \} > \rfloor \rangle \rceil".split()) _delims = _left_delims | _right_delims | _ambi_delims def __init__(self): p = types.SimpleNamespace() def set_names_and_parse_actions(): for key, val in vars(p).items(): if not key.startswith('_'): # Set names on everything -- very useful for debugging val.setName(key) # Set actions if hasattr(self, key): val.setParseAction(getattr(self, key)) # Root definitions. # In TeX parlance, a csname is a control sequence name (a "\foo"). def csnames(group, names): ends_with_alpha = [] ends_with_nonalpha = [] for name in names: if name[-1].isalpha(): ends_with_alpha.append(name) else: ends_with_nonalpha.append(name) return Regex(r"\\(?P<{}>(?:{})(?![A-Za-z]){})".format( group, "|".join(map(re.escape, ends_with_alpha)), "".join(f"|{s}" for s in map(re.escape, ends_with_nonalpha)), )) p.float_literal = Regex(r"[-+]?([0-9]+\.?[0-9]*|\.[0-9]+)") p.space = oneOf(self._space_widths)("space") p.style_literal = oneOf( [str(e.value) for e in self._MathStyle])("style_literal") p.symbol = Regex( r"[a-zA-Z0-9 +\-*/<>=:,.;!\?&'@()\[\]|\U00000080-\U0001ffff]" r"|\\[%${}\[\]_|]" + r"|\\(?:{})(?![A-Za-z])".format( "|".join(map(re.escape, tex2uni))) )("sym").leaveWhitespace() p.unknown_symbol = Regex(r"\\[A-Za-z]*")("name") p.font = csnames("font", self._fontnames) p.start_group = ( Optional(r"\math" + oneOf(self._fontnames)("font")) + "{") p.end_group = Literal("}") p.delim = oneOf(self._delims) set_names_and_parse_actions() # for root definitions. # Mutually recursive definitions. (Minimizing the number of Forward # elements is important for speed.) p.accent = Forward() p.auto_delim = Forward() p.binom = Forward() p.customspace = Forward() p.frac = Forward() p.dfrac = Forward() p.function = Forward() p.genfrac = Forward() p.group = Forward() p.operatorname = Forward() p.overline = Forward() p.overset = Forward() p.placeable = Forward() p.required_group = Forward() p.simple = Forward() p.optional_group = Forward() p.sqrt = Forward() p.subsuper = Forward() p.token = Forward() p.underset = Forward() set_names_and_parse_actions() # for mutually recursive definitions. p.customspace <<= cmd(r"\hspace", "{" + p.float_literal("space") + "}") p.accent <<= ( csnames("accent", [*self._accent_map, *self._wide_accents]) - p.placeable("sym")) p.function <<= csnames("name", self._function_names) p.operatorname <<= cmd( r"\operatorname", "{" + ZeroOrMore(p.simple | p.unknown_symbol)("name") + "}") p.group <<= p.start_group + ZeroOrMore(p.token)("group") + p.end_group p.optional_group <<= "{" + ZeroOrMore(p.token)("group") + "}" p.required_group <<= "{" + OneOrMore(p.token)("group") + "}" p.frac <<= cmd( r"\frac", p.required_group("num") + p.required_group("den")) p.dfrac <<= cmd( r"\dfrac", p.required_group("num") + p.required_group("den")) p.binom <<= cmd( r"\binom", p.required_group("num") + p.required_group("den")) p.genfrac <<= cmd( r"\genfrac", "{" + Optional(p.delim)("ldelim") + "}" + "{" + Optional(p.delim)("rdelim") + "}" + "{" + p.float_literal("rulesize") + "}" + "{" + Optional(p.style_literal)("style") + "}" + p.required_group("num") + p.required_group("den")) p.sqrt <<= cmd( r"\sqrt{value}", Optional("[" + OneOrMore(NotAny("]") + p.token)("root") + "]") + p.required_group("value")) p.overline <<= cmd(r"\overline", p.required_group("body")) p.overset <<= cmd( r"\overset", p.optional_group("annotation") + p.optional_group("body")) p.underset <<= cmd( r"\underset", p.optional_group("annotation") + p.optional_group("body")) p.placeable <<= ( p.accent # Must be before symbol as all accents are symbols | p.symbol # Must be second to catch all named symbols and single # chars not in a group | p.function | p.operatorname | p.group | p.frac | p.dfrac | p.binom | p.genfrac | p.overset | p.underset | p.sqrt | p.overline ) p.simple <<= ( p.space | p.customspace | p.font | p.subsuper ) p.subsuper <<= ( (Optional(p.placeable)("nucleus") + OneOrMore(oneOf(["_", "^"]) - p.placeable)("subsuper") + Regex("'*")("apostrophes")) | Regex("'+")("apostrophes") | (p.placeable("nucleus") + Regex("'*")("apostrophes")) ) p.token <<= ( p.simple | p.auto_delim | p.unknown_symbol # Must be last ) p.auto_delim <<= ( r"\left" - (p.delim("left") | Error("Expected a delimiter")) + ZeroOrMore(p.simple | p.auto_delim)("mid") + r"\right" - (p.delim("right") | Error("Expected a delimiter")) ) # Leaf definitions. p.math = OneOrMore(p.token) p.math_string = QuotedString('$', '\\', unquoteResults=False) p.non_math = Regex(r"(?:(?:\\[$])|[^$])*").leaveWhitespace() p.main = ( p.non_math + ZeroOrMore(p.math_string + p.non_math) + StringEnd() ) set_names_and_parse_actions() # for leaf definitions. self._expression = p.main self._math_expression = p.math # To add space to nucleus operators after sub/superscripts self._in_subscript_or_superscript = False def parse(self, s, fonts_object, fontsize, dpi): """ Parse expression *s* using the given *fonts_object* for output, at the given *fontsize* and *dpi*. Returns the parse tree of `Node` instances. """ self._state_stack = [ ParserState(fonts_object, 'default', 'rm', fontsize, dpi)] self._em_width_cache = {} try: result = self._expression.parseString(s) except ParseBaseException as err: # explain becomes a plain method on pyparsing 3 (err.explain(0)). raise ValueError("\n" + ParseException.explain(err, 0)) from None self._state_stack = None self._in_subscript_or_superscript = False # prevent operator spacing from leaking into a new expression self._em_width_cache = {} self._expression.resetCache() return result[0] def get_state(self): """Get the current `State` of the parser.""" return self._state_stack[-1] def pop_state(self): """Pop a `State` off of the stack.""" self._state_stack.pop() def push_state(self): """Push a new `State` onto the stack, copying the current state.""" self._state_stack.append(self.get_state().copy()) def main(self, s, loc, toks): return [Hlist(toks)] def math_string(self, s, loc, toks): return self._math_expression.parseString(toks[0][1:-1]) def math(self, s, loc, toks): hlist = Hlist(toks) self.pop_state() return [hlist] def non_math(self, s, loc, toks): s = toks[0].replace(r'\$', '$') symbols = [Char(c, self.get_state()) for c in s] hlist = Hlist(symbols) # We're going into math now, so set font to 'it' self.push_state() self.get_state().font = mpl.rcParams['mathtext.default'] return [hlist] float_literal = staticmethod(pyparsing_common.convertToFloat) def _make_space(self, percentage): # In TeX, an em (the unit usually used to measure horizontal lengths) # is not the width of the character 'm'; it is the same in different # font styles (e.g. roman or italic). Mathtext, however, uses 'm' in # the italic style so that horizontal spaces don't depend on the # current font style. state = self.get_state() key = (state.font, state.fontsize, state.dpi) width = self._em_width_cache.get(key) if width is None: metrics = state.fontset.get_metrics( 'it', mpl.rcParams['mathtext.default'], 'm', state.fontsize, state.dpi) width = metrics.advance self._em_width_cache[key] = width return Kern(width * percentage) _space_widths = { r'\,': 0.16667, # 3/18 em = 3 mu r'\thinspace': 0.16667, # 3/18 em = 3 mu r'\/': 0.16667, # 3/18 em = 3 mu r'\>': 0.22222, # 4/18 em = 4 mu r'\:': 0.22222, # 4/18 em = 4 mu r'\;': 0.27778, # 5/18 em = 5 mu r'\ ': 0.33333, # 6/18 em = 6 mu r'~': 0.33333, # 6/18 em = 6 mu, nonbreakable r'\enspace': 0.5, # 9/18 em = 9 mu r'\quad': 1, # 1 em = 18 mu r'\qquad': 2, # 2 em = 36 mu r'\!': -0.16667, # -3/18 em = -3 mu } def space(self, s, loc, toks): num = self._space_widths[toks["space"]] box = self._make_space(num) return [box] def customspace(self, s, loc, toks): return [self._make_space(toks["space"])] def symbol(self, s, loc, toks): c = toks["sym"] if c == "-": # "U+2212 minus sign is the preferred representation of the unary # and binary minus sign rather than the ASCII-derived U+002D # hyphen-minus, because minus sign is unambiguous and because it # is rendered with a more desirable length, usually longer than a # hyphen." (https://www.unicode.org/reports/tr25/) c = "\N{MINUS SIGN}" try: char = Char(c, self.get_state()) except ValueError as err: raise ParseFatalException(s, loc, "Unknown symbol: %s" % c) from err if c in self._spaced_symbols: # iterate until we find previous character, needed for cases # such as ${ -2}$, $ -2$, or $ -2$. prev_char = next((c for c in s[:loc][::-1] if c != ' '), '') # Binary operators at start of string should not be spaced if (c in self._binary_operators and (len(s[:loc].split()) == 0 or prev_char == '{' or prev_char in self._left_delims)): return [char] else: return [Hlist([self._make_space(0.2), char, self._make_space(0.2)], do_kern=True)] elif c in self._punctuation_symbols: prev_char = next((c for c in s[:loc][::-1] if c != ' '), '') next_char = next((c for c in s[loc + 1:] if c != ' '), '') # Do not space commas between brackets if c == ',': if prev_char == '{' and next_char == '}': return [char] # Do not space dots as decimal separators if c == '.' and prev_char.isdigit() and next_char.isdigit(): return [char] else: return [Hlist([char, self._make_space(0.2)], do_kern=True)] return [char] def unknown_symbol(self, s, loc, toks): raise ParseFatalException(s, loc, f"Unknown symbol: {toks['name']}") _accent_map = { r'hat': r'\circumflexaccent', r'breve': r'\combiningbreve', r'bar': r'\combiningoverline', r'grave': r'\combininggraveaccent', r'acute': r'\combiningacuteaccent', r'tilde': r'\combiningtilde', r'dot': r'\combiningdotabove', r'ddot': r'\combiningdiaeresis', r'dddot': r'\combiningthreedotsabove', r'ddddot': r'\combiningfourdotsabove', r'vec': r'\combiningrightarrowabove', r'"': r'\combiningdiaeresis', r"`": r'\combininggraveaccent', r"'": r'\combiningacuteaccent', r'~': r'\combiningtilde', r'.': r'\combiningdotabove', r'^': r'\circumflexaccent', r'overrightarrow': r'\rightarrow', r'overleftarrow': r'\leftarrow', r'mathring': r'\circ', } _wide_accents = set(r"widehat widetilde widebar".split()) def accent(self, s, loc, toks): state = self.get_state() thickness = state.get_current_underline_thickness() accent = toks["accent"] sym = toks["sym"] if accent in self._wide_accents: accent_box = AutoWidthChar( '\\' + accent, sym.width, state, char_class=Accent) else: accent_box = Accent(self._accent_map[accent], state) if accent == 'mathring': accent_box.shrink() accent_box.shrink() centered = HCentered([Hbox(sym.width / 4.0), accent_box]) centered.hpack(sym.width, 'exactly') return Vlist([ centered, Vbox(0., thickness * 2.0), Hlist([sym]) ]) def function(self, s, loc, toks): hlist = self.operatorname(s, loc, toks) hlist.function_name = toks["name"] return hlist def operatorname(self, s, loc, toks): self.push_state() state = self.get_state() state.font = 'rm' hlist_list = [] # Change the font of Chars, but leave Kerns alone name = toks["name"] for c in name: if isinstance(c, Char): c.font = 'rm' c._update_metrics() hlist_list.append(c) elif isinstance(c, str): hlist_list.append(Char(c, state)) else: hlist_list.append(c) next_char_loc = loc + len(name) + 1 if isinstance(name, ParseResults): next_char_loc += len('operatorname{}') next_char = next((c for c in s[next_char_loc:] if c != ' '), '') delimiters = self._delims | {'^', '_'} if (next_char not in delimiters and name not in self._overunder_functions): # Add thin space except when followed by parenthesis, bracket, etc. hlist_list += [self._make_space(self._space_widths[r'\,'])] self.pop_state() # if followed by a super/subscript, set flag to true # This flag tells subsuper to add space after this operator if next_char in {'^', '_'}: self._in_subscript_or_superscript = True else: self._in_subscript_or_superscript = False return Hlist(hlist_list) def start_group(self, s, loc, toks): self.push_state() # Deal with LaTeX-style font tokens if toks.get("font"): self.get_state().font = toks.get("font") return [] def group(self, s, loc, toks): grp = Hlist(toks.get("group", [])) return [grp] def required_group(self, s, loc, toks): return Hlist(toks.get("group", [])) optional_group = required_group def end_group(self, s, loc, toks): self.pop_state() return [] def font(self, s, loc, toks): self.get_state().font = toks["font"] return [] def is_overunder(self, nucleus): if isinstance(nucleus, Char): return nucleus.c in self._overunder_symbols elif isinstance(nucleus, Hlist) and hasattr(nucleus, 'function_name'): return nucleus.function_name in self._overunder_functions return False def is_dropsub(self, nucleus): if isinstance(nucleus, Char): return nucleus.c in self._dropsub_symbols return False def is_slanted(self, nucleus): if isinstance(nucleus, Char): return nucleus.is_slanted() return False def is_between_brackets(self, s, loc): return False def subsuper(self, s, loc, toks): nucleus = toks.get("nucleus", Hbox(0)) subsuper = toks.get("subsuper", []) napostrophes = len(toks.get("apostrophes", [])) if not subsuper and not napostrophes: return nucleus sub = super = None while subsuper: op, arg, *subsuper = subsuper if op == '_': if sub is not None: raise ParseFatalException("Double subscript") sub = arg else: if super is not None: raise ParseFatalException("Double superscript") super = arg state = self.get_state() rule_thickness = state.fontset.get_underline_thickness( state.font, state.fontsize, state.dpi) xHeight = state.fontset.get_xheight( state.font, state.fontsize, state.dpi) if napostrophes: if super is None: super = Hlist([]) for i in range(napostrophes): super.children.extend(self.symbol(s, loc, {"sym": "\\prime"})) # kern() and hpack() needed to get the metrics right after # extending super.kern() super.hpack() # Handle over/under symbols, such as sum or prod if self.is_overunder(nucleus): vlist = [] shift = 0. width = nucleus.width if super is not None: super.shrink() width = max(width, super.width) if sub is not None: sub.shrink() width = max(width, sub.width) vgap = rule_thickness * 3.0 if super is not None: hlist = HCentered([super]) hlist.hpack(width, 'exactly') vlist.extend([hlist, Vbox(0, vgap)]) hlist = HCentered([nucleus]) hlist.hpack(width, 'exactly') vlist.append(hlist) if sub is not None: hlist = HCentered([sub]) hlist.hpack(width, 'exactly') vlist.extend([Vbox(0, vgap), hlist]) shift = hlist.height + vgap + nucleus.depth vlist = Vlist(vlist) vlist.shift_amount = shift result = Hlist([vlist]) return [result] # We remove kerning on the last character for consistency (otherwise # it will compute kerning based on non-shrunk characters and may put # them too close together when superscripted) # We change the width of the last character to match the advance to # consider some fonts with weird metrics: e.g. stix's f has a width of # 7.75 and a kerning of -4.0 for an advance of 3.72, and we want to put # the superscript at the advance last_char = nucleus if isinstance(nucleus, Hlist): new_children = nucleus.children if len(new_children): # remove last kern if (isinstance(new_children[-1], Kern) and hasattr(new_children[-2], '_metrics')): new_children = new_children[:-1] last_char = new_children[-1] if hasattr(last_char, '_metrics'): last_char.width = last_char._metrics.advance # create new Hlist without kerning nucleus = Hlist(new_children, do_kern=False) else: if isinstance(nucleus, Char): last_char.width = last_char._metrics.advance nucleus = Hlist([nucleus]) # Handle regular sub/superscripts constants = _get_font_constant_set(state) lc_height = last_char.height lc_baseline = 0 if self.is_dropsub(last_char): lc_baseline = last_char.depth # Compute kerning for sub and super superkern = constants.delta * xHeight subkern = constants.delta * xHeight if self.is_slanted(last_char): superkern += constants.delta * xHeight superkern += (constants.delta_slanted * (lc_height - xHeight * 2. / 3.)) if self.is_dropsub(last_char): subkern = (3 * constants.delta - constants.delta_integral) * lc_height superkern = (3 * constants.delta + constants.delta_integral) * lc_height else: subkern = 0 if super is None: # node757 x = Hlist([Kern(subkern), sub]) x.shrink() if self.is_dropsub(last_char): shift_down = lc_baseline + constants.subdrop * xHeight else: shift_down = constants.sub1 * xHeight x.shift_amount = shift_down else: x = Hlist([Kern(superkern), super]) x.shrink() if self.is_dropsub(last_char): shift_up = lc_height - constants.subdrop * xHeight else: shift_up = constants.sup1 * xHeight if sub is None: x.shift_amount = -shift_up else: # Both sub and superscript y = Hlist([Kern(subkern), sub]) y.shrink() if self.is_dropsub(last_char): shift_down = lc_baseline + constants.subdrop * xHeight else: shift_down = constants.sub2 * xHeight # If sub and superscript collide, move super up clr = (2.0 * rule_thickness - ((shift_up - x.depth) - (y.height - shift_down))) if clr > 0.: shift_up += clr x = Vlist([ x, Kern((shift_up - x.depth) - (y.height - shift_down)), y]) x.shift_amount = shift_down if not self.is_dropsub(last_char): x.width += constants.script_space * xHeight # Do we need to add a space after the nucleus? # To find out, check the flag set by operatorname spaced_nucleus = [nucleus, x] if self._in_subscript_or_superscript: spaced_nucleus += [self._make_space(self._space_widths[r'\,'])] self._in_subscript_or_superscript = False result = Hlist(spaced_nucleus) return [result] def _genfrac(self, ldelim, rdelim, rule, style, num, den): state = self.get_state() thickness = state.get_current_underline_thickness() for _ in range(style.value): num.shrink() den.shrink() cnum = HCentered([num]) cden = HCentered([den]) width = max(num.width, den.width) cnum.hpack(width, 'exactly') cden.hpack(width, 'exactly') vlist = Vlist([cnum, # numerator Vbox(0, thickness * 2.0), # space Hrule(state, rule), # rule Vbox(0, thickness * 2.0), # space cden # denominator ]) # Shift so the fraction line sits in the middle of the # equals sign metrics = state.fontset.get_metrics( state.font, mpl.rcParams['mathtext.default'], '=', state.fontsize, state.dpi) shift = (cden.height - ((metrics.ymax + metrics.ymin) / 2 - thickness * 3.0)) vlist.shift_amount = shift result = [Hlist([vlist, Hbox(thickness * 2.)])] if ldelim or rdelim: if ldelim == '': ldelim = '.' if rdelim == '': rdelim = '.' return self._auto_sized_delimiter(ldelim, result, rdelim) return result def style_literal(self, s, loc, toks): return self._MathStyle(int(toks["style_literal"])) def genfrac(self, s, loc, toks): return self._genfrac( toks.get("ldelim", ""), toks.get("rdelim", ""), toks["rulesize"], toks.get("style", self._MathStyle.TEXTSTYLE), toks["num"], toks["den"]) def frac(self, s, loc, toks): return self._genfrac( "", "", self.get_state().get_current_underline_thickness(), self._MathStyle.TEXTSTYLE, toks["num"], toks["den"]) def dfrac(self, s, loc, toks): return self._genfrac( "", "", self.get_state().get_current_underline_thickness(), self._MathStyle.DISPLAYSTYLE, toks["num"], toks["den"]) def binom(self, s, loc, toks): return self._genfrac( "(", ")", 0, self._MathStyle.TEXTSTYLE, toks["num"], toks["den"]) def _genset(self, s, loc, toks): annotation = toks["annotation"] body = toks["body"] thickness = self.get_state().get_current_underline_thickness() annotation.shrink() cannotation = HCentered([annotation]) cbody = HCentered([body]) width = max(cannotation.width, cbody.width) cannotation.hpack(width, 'exactly') cbody.hpack(width, 'exactly') vgap = thickness * 3 if s[loc + 1] == "u": # \underset vlist = Vlist([cbody, # body Vbox(0, vgap), # space cannotation # annotation ]) # Shift so the body sits in the same vertical position vlist.shift_amount = cbody.depth + cannotation.height + vgap else: # \overset vlist = Vlist([cannotation, # annotation Vbox(0, vgap), # space cbody # body ]) # To add horizontal gap between symbols: wrap the Vlist into # an Hlist and extend it with an Hbox(0, horizontal_gap) return vlist overset = underset = _genset def sqrt(self, s, loc, toks): root = toks.get("root") body = toks["value"] state = self.get_state() thickness = state.get_current_underline_thickness() # Determine the height of the body, and add a little extra to # the height so it doesn't seem cramped height = body.height - body.shift_amount + thickness * 5.0 depth = body.depth + body.shift_amount check = AutoHeightChar(r'\__sqrt__', height, depth, state, always=True) height = check.height - check.shift_amount depth = check.depth + check.shift_amount # Put a little extra space to the left and right of the body padded_body = Hlist([Hbox(2 * thickness), body, Hbox(2 * thickness)]) rightside = Vlist([Hrule(state), Glue('fill'), padded_body]) # Stretch the glue between the hrule and the body rightside.vpack(height + (state.fontsize * state.dpi) / (100.0 * 12.0), 'exactly', depth) # Add the root and shift it upward so it is above the tick. # The value of 0.6 is a hard-coded hack ;) if not root: root = Box(check.width * 0.5, 0., 0.) else: root = Hlist(root) root.shrink() root.shrink() root_vlist = Vlist([Hlist([root])]) root_vlist.shift_amount = -height * 0.6 hlist = Hlist([root_vlist, # Root # Negative kerning to put root over tick Kern(-check.width * 0.5), check, # Check rightside]) # Body return [hlist] def overline(self, s, loc, toks): body = toks["body"] state = self.get_state() thickness = state.get_current_underline_thickness() height = body.height - body.shift_amount + thickness * 3.0 depth = body.depth + body.shift_amount # Place overline above body rightside = Vlist([Hrule(state), Glue('fill'), Hlist([body])]) # Stretch the glue between the hrule and the body rightside.vpack(height + (state.fontsize * state.dpi) / (100.0 * 12.0), 'exactly', depth) hlist = Hlist([rightside]) return [hlist] def _auto_sized_delimiter(self, front, middle, back): state = self.get_state() if len(middle): height = max(x.height for x in middle) depth = max(x.depth for x in middle) factor = None else: height = 0 depth = 0 factor = 1.0 parts = [] # \left. and \right. aren't supposed to produce any symbols if front != '.': parts.append( AutoHeightChar(front, height, depth, state, factor=factor)) parts.extend(middle) if back != '.': parts.append( AutoHeightChar(back, height, depth, state, factor=factor)) hlist = Hlist(parts) return hlist def auto_delim(self, s, loc, toks): return self._auto_sized_delimiter( toks["left"], # if "mid" in toks ... can be removed when requiring pyparsing 3. toks["mid"].asList() if "mid" in toks else [], toks["right"])