Mark some slow tests as slow

src/sage/rings/number_field/number_field_rel.py

@@ -2467,7 +2467,7 @@
         EXAMPLES::
 
             sage: P.<a,b,c> = QQ[2^(1/2), 2^(1/3), 3^(1/2)]                             # needs sage.symbolic
-            sage: R = P.order([a,b,c]); R                                               # needs sage.symbolic
+            sage: R = P.order([a,b,c]); R                                               # long time (83s), needs sage.symbolic
             Relative Order generated by
              [((-36372*sqrt3 + 371270)*a^2 + (-89082*sqrt3 + 384161)*a - 422504*sqrt3 - 46595)*sqrt2 + (303148*sqrt3 - 89080)*a^2 + (313664*sqrt3 - 218211)*a - 38053*sqrt3 - 1034933,
               ((-65954*sqrt3 + 323491)*a^2 + (-110591*sqrt3 + 350011)*a - 351557*sqrt3 + 77507)*sqrt2 + (264138*sqrt3 - 161552)*a^2 + (285784*sqrt3 - 270906)*a + 63287*sqrt3 - 861151,
@@ -2478,7 +2478,7 @@
 
         The base ring of an order in a relative extension is still `\ZZ`.::
 
             sage: R.base_ring()                                                         # needs sage.symbolic
             Integer Ring
 
         One must give enough generators to generate a ring of finite index

src/sage/rings/polynomial/polynomial_element.pyx

@@ -5211,13 +5211,13 @@ cdef class Polynomial(CommutativePolynomial):
             sage: # needs sage.rings.finite_rings
             sage: P.<x> = PolynomialRing(GF(401^13, 'a'))
             sage: t = 2*x^14 - 5 + 6*x
-            sage: t.splitting_field('b')
+            sage: t.splitting_field('b')                                                # long time -- 16s
             Finite Field in b of size 401^104
             sage: t = 24*x^13 + 2*x^12 + 14
-            sage: t.splitting_field('b')
+            sage: t.splitting_field('b')                                                # long time -- 39s
             Finite Field in b of size 401^156
             sage: t = x^56 - 14*x^3
-            sage: t.splitting_field('b')
+            sage: t.splitting_field('b')                                                # long time -- 2s
             Finite Field in b of size 401^52
 
             sage: R.<x> = QQ[]

src/sage/rings/polynomial/polynomial_quotient_ring_element.py

@@ -721,6 +721,7 @@ def minpoly(self):
 
         We make sure that the previous example works on random examples::
 
+            sage: # long time
             sage: # needs sage.rings.finite_rings
             sage: p = random_prime(50)
             sage: K.<u> = GF((p, randrange(1,20)))

src/sage/rings/tate_algebra_ideal.pyx

@@ -623,7 +623,7 @@
 
     TESTS::
 
-        sage: cython(                                                                   # needs sage.misc.cython
+        sage: cython(                                                                   # long time 6.5s, needs sage.misc.cython
         ....: '''
         ....: from sage.rings.tate_algebra_ideal cimport regular_reduce
         ....: def python_regular_reduce(gb, s, v, stopval):
@@ -638,10 +638,10 @@
         sage: p1 = (tx, x^3 + 9*x*y)
         sage: p2 = (ty, x*y + 3*x^2*y)
 
         sage: python_regular_reduce([p1,p2], tx*ty, v, 8)   # indirect doctest          # needs sage.misc.cython
         (2 + O(3^8))*x^2*y + (1 + O(3^8))*x + (1 + O(3^8))*y + O(3^8 * <x, y>)
 
         sage: python_regular_reduce([p1,p2], tx, v, 8)      # indirect doctest          # needs sage.misc.cython
         (2 + 2*3 + 2*3^2 + 2*3^3 + 2*3^4 + 2*3^5 + 2*3^6 + 2*3^7 + O(3^8))*x^3
         + (2 + O(3^8))*x^2*y + (1 + O(3^8))*x + (1 + O(3^8))*y + O(3^8 * <x, y>)
     """

src/sage/schemes/elliptic_curves/ell_field.py

@@ -1419,10 +1419,10 @@ def kernel_polynomial_from_point(self, P, *, algorithm=None):
             sage: from sage.schemes.elliptic_curves.ell_field import EllipticCurve_field, point_of_order
             sage: p = 2^127 - 1
             sage: E = EllipticCurve(GF(p), [1,0])
-            sage: P = point_of_order(E, 31)
-            sage: %timeit E.kernel_polynomial_from_point(P, algorithm='basic')    # not tested
+            sage: P = point_of_order(E, 31)                                             # long time -- 8.5s
+            sage: %timeit E.kernel_polynomial_from_point(P, algorithm='basic')          # not tested
             4.38 ms ± 13.7 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
-            sage: %timeit E.kernel_polynomial_from_point(P, algorithm='minpoly')  # not tested
+            sage: %timeit E.kernel_polynomial_from_point(P, algorithm='minpoly')        # not tested
             854 µs ± 1.56 µs per loop (mean ± std. dev. of 7 runs, 1,000 loops each)
 
         Example of finding all the rational isogenies using this method::

src/sage/schemes/elliptic_curves/ell_number_field.py

@@ -805,7 +805,7 @@ def _scale_by_units(self):
             sage: K.<a> = QuadraticField(4569)
             sage: j = 46969655/32768
             sage: E = EllipticCurve(j=K(j))
-            sage: C = E.isogeny_class()
+            sage: C = E.isogeny_class()                                                 # long time -- 9.5s
         """
         K = self.base_field()
         r1, r2 = K.signature()

src/sage/schemes/elliptic_curves/isogeny_class.py

@@ -1399,7 +1399,7 @@ def possible_isogeny_degrees(E, algorithm='Billerey', max_l=None,
     Over an extension field::
 
         sage: E3 = E.change_ring(CyclotomicField(3))
-        sage: possible_isogeny_degrees(E3)
+        sage: possible_isogeny_degrees(E3)                                              # long time -- 5s
         [5]
         sage: [phi.degree() for phi in E3.isogenies_prime_degree()]
         [5, 5]
@@ -1421,7 +1421,7 @@ def possible_isogeny_degrees(E, algorithm='Billerey', max_l=None,
 
         sage: K.<a> = NumberField(x^4 - 5*x^2 + 3)
         sage: E = EllipticCurve(K, [a^2 - 2, -a^2 + 3, a^2 - 2, -50*a^2 + 35, 95*a^2 - 67])
-        sage: possible_isogeny_degrees(E, exact=False, algorithm='Billerey')
+        sage: possible_isogeny_degrees(E, exact=False, algorithm='Billerey')            # long time -- 6.5s
         [2, 5]
         sage: possible_isogeny_degrees(E, exact=False, algorithm='Larson')
         [2, 5]
@@ -1432,7 +1432,7 @@ def possible_isogeny_degrees(E, algorithm='Billerey', max_l=None,
 
     This function only returns the primes which are isogeny degrees::
 
-        sage: Set(E.isogeny_class().matrix().list())
+        sage: Set(E.isogeny_class().matrix().list())                                    # long time -- 7s
         {1, 2, 4, 5, 20, 10}
 
     For curves with CM by a quadratic order of class number greater