matplotlib
diff --git a/‎lib/matplotlib/_mathtext.py‎
Lines changed: 35 additions & 2 deletions b/‎lib/matplotlib/_mathtext.py‎
Lines changed: 35 additions & 2 deletions
diff --git a/‎lib/matplotlib/tests/baseline_images/test_mathtext/mathtext1_dejavusans_07.png‎
6.36 KB b/‎lib/matplotlib/tests/baseline_images/test_mathtext/mathtext1_dejavusans_07.png‎
6.36 KB
diff --git a/‎lib/matplotlib/tests/test_mathtext.py‎
Lines changed: 1 addition & 0 deletions b/‎lib/matplotlib/tests/test_mathtext.py‎
Lines changed: 1 addition & 0 deletions
@@ -18,7 +18,7 @@
     Empty, Forward, Literal, NotAny, oneOf, OneOrMore, Optional,
     ParseBaseException, ParseException, ParseExpression, ParseFatalException,
     ParserElement, ParseResults, QuotedString, Regex, StringEnd, ZeroOrMore,
-    pyparsing_common)
+    pyparsing_common, Group)
 
 import matplotlib as mpl
 from . import cbook
@@ -27,6 +27,11 @@
 from .font_manager import FontProperties, findfont, get_font
 from .ft2font import FT2Image, KERNING_DEFAULT
 
+from pyparsing import __version_info__ as pyparsing_version
+if pyparsing_version < (3, 0):
+    from pyparsing import nestedExpr as nested_expr
+else:
+    from pyparsing import nested_expr
 
 ParserElement.enablePackrat()
 _log = logging.getLogger("matplotlib.mathtext")
@@ -1865,7 +1870,7 @@ def csnames(group, names):
             + r"|\\(?:{})(?![A-Za-z])".format(
                 "|".join(map(re.escape, tex2uni)))
         )("sym").leaveWhitespace()
-        p.unknown_symbol = Regex(r"\\[A-Za-z]*")("name")
+        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")) + "{"
@@ -1925,6 +1930,11 @@ def csnames(group, names):
 
         p.text = cmd(r"\text", QuotedString('{', '\\', endQuoteChar="}"))
 
+        p.substack = cmd(r"\substack",
+                           nested_expr(opener="{", closer="}",
+                                       content=Group(OneOrMore(p.token)) +
+                                       ZeroOrMore(Literal("\\\\").suppress()))("parts"))
+
         p.subsuper = (
             (Optional(p.placeable)("nucleus")
              + OneOrMore(oneOf(["_", "^"]) - p.placeable)("subsuper")
@@ -1963,6 +1973,7 @@ def csnames(group, names):
             | p.overline
             | p.text
             | p.boldsymbol
+            | p.substack
         )
 
         p.auto_delim    <<= (
@@ -2637,3 +2648,25 @@ def boldsymbol(self, s, loc, toks):
         self.pop_state()
 
         return Hlist(hlist)
+
+    def substack(self, s, loc, toks):
+        parts = toks["parts"]
+        state = self.get_state()
+        thickness = state.get_current_underline_thickness()
+        vlist = []
+
+        hlist = [Hlist(k) for k in parts[0]]
+        max_width = max(map(lambda c: c.width, hlist))
+
+        for sub in hlist:
+            cp = HCentered([sub])
+            cp.hpack(max_width, 'exactly')
+            vlist.append(cp)
+
+        vlist = [val for pair in zip(vlist,
+                                     [Vbox(0, thickness * 2)] *
+                                     len(vlist)) for val in pair]
+        del vlist[-1]
+        vlt = Vlist(vlist)
+        result = [Hlist([vlt])]
+        return result
@@ -136,6 +136,7 @@
     r'$\text{text}_{\text{sub}}^{\text{sup}} + \text{\$foo\$} + \frac{\text{num}}{\mathbf{\text{den}}}\text{with space, curly brackets \{\}, and dash -}$',
     r'$\boldsymbol{abcde} \boldsymbol{+} \boldsymbol{\Gamma + \Omega} \boldsymbol{01234} \boldsymbol{\alpha * \beta}$',
     r'$\left\lbrace\frac{\left\lbrack A^b_c\right\rbrace}{\left\leftbrace D^e_f \right\rbrack}\right\rightbrace\ \left\leftparen\max_{x} \left\lgroup \frac{A}{B}\right\rgroup \right\rightparen$',
+    r'$\sum_{\substack{k = 1\\ k \neq \lfloor n/2\rfloor}}^{n}P(i,j) \sum_{\substack{i \neq 0\\ -1 \leq i \leq 3\\ 1 \leq j \leq 5}} F^i(x,y) \sum_{\substack{\left \lfloor \frac{n}{2} \right\rfloor}} F(n)$',
 ]
 
 digits = "0123456789"
Original file line number	Diff line number	Diff line change
`@@ -136,6 +136,7 @@`
`136`	`136`	`r'$\text{text}_{\text{sub}}^{\text{sup}} + \text{\$foo\$} + \frac{\text{num}}{\mathbf{\text{den}}}\text{with space, curly brackets \{\}, and dash -}$',`
`137`	`137`	`r'$\boldsymbol{abcde} \boldsymbol{+} \boldsymbol{\Gamma + \Omega} \boldsymbol{01234} \boldsymbol{\alpha * \beta}$',`
`138`	`138`	`r'$\left\lbrace\frac{\left\lbrack A^b_c\right\rbrace}{\left\leftbrace D^e_f \right\rbrack}\right\rightbrace\ \left\leftparen\max_{x} \left\lgroup \frac{A}{B}\right\rgroup \right\rightparen$',`
	`139`	`+ r'$\sum_{\substack{k = 1\\ k \neq \lfloor n/2\rfloor}}^{n}P(i,j) \sum_{\substack{i \neq 0\\ -1 \leq i \leq 3\\ 1 \leq j \leq 5}} F^i(x,y) \sum_{\substack{\left \lfloor \frac{n}{2} \right\rfloor}} F(n)$',`
`139`	`140`	`]`
`140`	`141`
`141`	`142`	`digits = "0123456789"`