matplotlib · anntzer · Apr 21, 2023 · Mar 1, 2023
diff --git a/doc/users/next_whats_new/updated_mathtext.rst b/doc/users/next_whats_new/updated_mathtext.rst
@@ -0,0 +1,14 @@
+Bold-italic mathtext command ``\mathbfit``
+-----------------------------------------------------
+
+Supports use of bold-italic font style in mathtext using the ``\mathbfit{}`` command:
+
+To change font to bold and italic enclose the text in a font command as
+shown:
+
+.. code-block::
+
+    r'$\mathbfit{\eta \leq C(\delta(\eta))}$
+
+.. math::
+   \mathbfit{\eta \leq C(\delta(\eta))}
diff --git a/galleries/users_explain/text/mathtext.py b/galleries/users_explain/text/mathtext.py
@@ -225,6 +225,7 @@
     ``\mathfrak{Fraktur}``           :math-stix:`\mathfrak{Fraktur}`
     ``\mathsf{sansserif}``           :math-stix:`\mathsf{sansserif}`
     ``\mathrm{\mathsf{sansserif}}``  :math-stix:`\mathrm{\mathsf{sansserif}}`
+    ``\mathbfit{bolditalic}``        :math-stix:`\mathbfit{bolditalic}`
     ================================ =========================================
 
 There are also five global "font sets" to choose from, which are
@@ -290,7 +291,8 @@
     ``mathtext.it``                ``\mathit{}`` or default italic
     ``mathtext.rm``                ``\mathrm{}`` Roman (upright)
     ``mathtext.tt``                ``\mathtt{}`` Typewriter (monospace)
-    ``mathtext.bf``                ``\mathbf{}`` bold italic
+    ``mathtext.bf``                ``\mathbf{}`` bold
+    ``mathtext.bfit``              ``\mathbfit{}`` bold italic
     ``mathtext.cal``               ``\mathcal{}`` calligraphic
     ``mathtext.sf``                ``\mathsf{}`` sans-serif
     ============================== =================================

diff --git a/lib/matplotlib/_mathtext.py b/lib/matplotlib/_mathtext.py
@@ -484,7 +484,7 @@ def __init__(self, *args, **kwargs):
 
         super().__init__(*args, **kwargs)
         self.fontmap = {}
-        for texfont in "cal rm tt it bf sf".split():
+        for texfont in "cal rm tt it bf sf bfit".split():
             prop = mpl.rcParams['mathtext.' + texfont]
             font = findfont(prop)
             self.fontmap[texfont] = font
@@ -631,6 +631,7 @@ class DejaVuSerifFonts(DejaVuFonts):
         'rm': 'DejaVu Serif',
         'it': 'DejaVu Serif:italic',
         'bf': 'DejaVu Serif:weight=bold',
+        'bfit': 'DejaVu Serif:italic:bold',
         'sf': 'DejaVu Sans',
         'tt': 'DejaVu Sans Mono',
         'ex': 'DejaVu Serif Display',
@@ -648,6 +649,7 @@ class DejaVuSansFonts(DejaVuFonts):
         'rm': 'DejaVu Sans',
         'it': 'DejaVu Sans:italic',
         'bf': 'DejaVu Sans:weight=bold',
+        'bfit': 'DejaVu Sans:italic:bold',
         'sf': 'DejaVu Sans',
         'tt': 'DejaVu Sans Mono',
         'ex': 'DejaVu Sans Display',
@@ -671,6 +673,7 @@ class StixFonts(UnicodeFonts):
         'rm': 'STIXGeneral',
         'it': 'STIXGeneral:italic',
         'bf': 'STIXGeneral:weight=bold',
+        'bfit': 'STIXGeneral:italic:bold',
         'nonunirm': 'STIXNonUnicode',
         'nonuniit': 'STIXNonUnicode:italic',
         'nonunibf': 'STIXNonUnicode:weight=bold',
@@ -736,7 +739,7 @@ def _map_virtual_font(self, fontname, font_class, uniindex):
             uniindex = stix_glyph_fixes.get(uniindex, uniindex)
 
         # Handle private use area glyphs
-        if fontname in ('it', 'rm', 'bf') and 0xe000 <= uniindex <= 0xf8ff:
+        if fontname in ('it', 'rm', 'bf', 'bfit') and 0xe000 <= uniindex <= 0xf8ff:
             fontname = 'nonuni' + fontname
 
         return fontname, uniindex
@@ -1665,7 +1668,7 @@ def font(self):
 
     @font.setter
     def font(self, name):
-        if name in ('rm', 'it', 'bf'):
+        if name in ('rm', 'it', 'bf', 'bfit'):
             self.font_class = name
         self._font = name
 
@@ -1771,7 +1774,8 @@ class _MathStyle(enum.Enum):
 
     _dropsub_symbols = set(r'''\int \oint'''.split())
 
-    _fontnames = set("rm cal it tt sf bf default bb frak scr regular".split())
+    _fontnames = set("rm cal it tt sf bf bfit "
+                     "default bb frak scr regular".split())
 
     _function_names = set("""
       arccos csc ker min arcsin deg lg Pr arctan det lim sec arg dim

diff --git a/lib/matplotlib/_mathtext_data.py b/lib/matplotlib/_mathtext_data.py
@@ -1210,6 +1210,13 @@
             (0x2202, 0x2202, 'bf', 0x1d789), # partial differential
             (0x2207, 0x2207, 'bf', 0x1d76f), # \Nabla
             ],
+        'bfit':
+            [
+            (0x0041, 0x005a, 'bfit', 0x1d468), # A-Z
+            (0x0061, 0x007a, 'bfit', 0x1d482), # a-z
+            (0x0393, 0x03a9, 'bfit', 0x1d71e), # \Gamma-\Omega
+            (0x03b1, 0x03c9, 'bfit', 0x1d736), # \alpha-\omega
+            ],
         },
     'tt':
         [

diff --git a/lib/matplotlib/mpl-data/matplotlibrc b/lib/matplotlib/mpl-data/matplotlibrc
@@ -340,6 +340,7 @@
 ## settings which map a TeX font name to a fontconfig font pattern.  (These
 ## settings are not used for other font sets.)
 #mathtext.bf:  sans:bold
+#mathtext.bfit: sans:italic:bold
 #mathtext.cal: cursive
 #mathtext.it:  sans:italic
 #mathtext.rm:  sans

diff --git a/lib/matplotlib/rcsetup.py b/lib/matplotlib/rcsetup.py
@@ -937,10 +937,11 @@ def _convert_validator_spec(key, conv):
     "mathtext.tt":             validate_font_properties,
     "mathtext.it":             validate_font_properties,
     "mathtext.bf":             validate_font_properties,
+    "mathtext.bfit":           validate_font_properties,
     "mathtext.sf":             validate_font_properties,
     "mathtext.fontset":        ["dejavusans", "dejavuserif", "cm", "stix",
                                 "stixsans", "custom"],
-    "mathtext.default":        ["rm", "cal", "it", "tt", "sf", "bf", "default",
+    "mathtext.default":        ["rm", "cal", "bfit", "it", "tt", "sf", "bf", "default",
                                 "bb", "frak", "scr", "regular"],
     "mathtext.fallback":       _validate_mathtext_fallback,
 

diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_cm_60.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_cm_60.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_cm_61.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_cm_61.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_cm_62.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_cm_62.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_cm_63.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_cm_63.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_cm_64.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_cm_64.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavusans_60.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavusans_60.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavusans_61.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavusans_61.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavusans_62.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavusans_62.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavusans_63.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavusans_63.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavusans_64.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavusans_64.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavuserif_60.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavuserif_60.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavuserif_61.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavuserif_61.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavuserif_62.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavuserif_62.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavuserif_63.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavuserif_63.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavuserif_64.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_dejavuserif_64.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stix_60.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stix_60.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stix_61.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stix_61.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stix_62.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stix_62.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stix_63.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stix_63.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stix_64.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stix_64.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stixsans_60.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stixsans_60.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stixsans_61.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stixsans_61.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stixsans_62.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stixsans_62.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stixsans_63.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stixsans_63.png
diff --git a/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stixsans_64.png b/lib/matplotlib/tests/baseline_images/test_mathtext/mathfont_stixsans_64.png
diff --git a/lib/matplotlib/tests/test_mathtext.py b/lib/matplotlib/tests/test_mathtext.py
@@ -172,7 +172,8 @@
     (['mathscr'], [uppercase, lowercase]),
     (['mathsf'], [digits, uppercase, lowercase]),
     (['mathrm', 'mathsf'], [digits, uppercase, lowercase]),
-    (['mathbf', 'mathsf'], [digits, uppercase, lowercase])
+    (['mathbf', 'mathsf'], [digits, uppercase, lowercase]),
+    (['mathbfit'], all),
     ]
 
 font_tests: list[None | str] = []
@@ -426,6 +427,7 @@ def test_mathtext_fallback(fallback, fontlist):
     mpl.rcParams['mathtext.rm'] = 'mpltest'
     mpl.rcParams['mathtext.it'] = 'mpltest:italic'
     mpl.rcParams['mathtext.bf'] = 'mpltest:bold'
+    mpl.rcParams['mathtext.bfit'] = 'mpltest:italic:bold'
     mpl.rcParams['mathtext.fallback'] = fallback
 
     test_str = r'a$A\AA\breve\gimel$'