From 56ee208e59725b45e06d4d0f0bd0e90811e03664 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fr=C3=A9d=C3=A9ric=20Chapoton?= <chapoton@unistra.fr>
Date: Sat, 11 Jun 2022 19:03:59 +0200
Subject: [PATCH] latex for elements of quotient rings

---
 src/sage/rings/quotient_ring_element.py | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/src/sage/rings/quotient_ring_element.py b/src/sage/rings/quotient_ring_element.py
index 7a3790f744b..69df8d3319e 100644
--- a/src/sage/rings/quotient_ring_element.py
+++ b/src/sage/rings/quotient_ring_element.py
@@ -224,6 +224,31 @@ def _repr_(self):
         with localvars(R, P.variable_names(), normalize=False):
             return str(self.__rep)
 
+    def _latex_(self):
+        """
+        Return the LaTeX representation as a string.
+
+        EXAMPLES::
+
+            sage: R = PolynomialRing(QQ, 'a, b, c')
+            sage: a = R.gen(0)
+            sage: I = R.ideal(a**2 + a + 1)
+            sage: S = R.quotient(I, names=R.variable_names())
+            sage: a = S.gen(0)
+            sage: latex(a)
+            a
+        """
+        from sage.structure.parent_gens import localvars
+        P = self.parent()
+        R = P.cover_ring()
+        # see _repr_ above for the idea
+        try:
+            P.variable_names()
+        except ValueError:
+            return self.__rep._latex_()
+        with localvars(R, P.variable_names(), normalize=False):
+            return self.__rep._latex_()
+
     def __pari__(self):
         """
         The Pari representation of this quotient element.