gh-35818: fully get rid of xrange() in pyx files
    
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### 📚 Description

replace all remaining xrange by range

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URL: #35818
Reported by: Frédéric Chapoton
Reviewer(s): Matthias Köppe

Author: Release Manager

src/sage/algebras/letterplace/free_algebra_letterplace.pyx

@@ -594,7 +594,7 @@ cdef class FreeAlgebra_letterplace(Algebra):
         cdef list tmp
         for i from 0<=i<nblocks:
             base = i*ngens
-            tmp = [(j,E[base+j]) for j in xrange(ngens) if E[base+j]]
+            tmp = [(j,E[base+j]) for j in range(ngens) if E[base+j]]
             if not tmp:
                 continue
             var_ind, exp = tmp[0]
@@ -627,7 +627,7 @@ cdef class FreeAlgebra_letterplace(Algebra):
         cdef list names = self.latex_variable_names()
         for i from 0<=i<nblocks:
             base = i*ngens
-            tmp = [(j,E[base+j]) for j in xrange(ngens) if E[base+j]]
+            tmp = [(j,E[base+j]) for j in range(ngens) if E[base+j]]
             if not tmp:
                 continue
             var_ind, exp = tmp[0]

src/sage/algebras/quatalg/quaternion_algebra_cython.pyx

@@ -226,9 +226,9 @@ def rational_quaternions_from_integral_matrix_and_denom(A, Matrix_integer_dense
     mpz_init(tmp)
 
     if reverse:
-        rng = xrange(H.nrows()-1, -1, -1)
+        rng = range(H.nrows()-1, -1, -1)
     else:
-        rng = xrange(H.nrows())
+        rng = range(H.nrows())
 
     for i in rng:
         x = <QuaternionAlgebraElement_rational_field> QuaternionAlgebraElement_rational_field.__new__(QuaternionAlgebraElement_rational_field)

src/sage/graphs/convexity_properties.pyx

@@ -435,7 +435,7 @@ cdef class ConvexityProperties:
         p.add_variables(self._n, 0, None, True, False, False, 1, None)
 
         # We know that at least 2 vertices are required to cover the whole graph
-        p.add_linear_constraint([(i, 1) for i in xrange(self._n)], 2, None)
+        p.add_linear_constraint([(i, 1) for i in range(self._n)], 2, None)
 
         # The set of vertices generated by the current LP solution
         cdef bitset_t current_hull

src/sage/graphs/generic_graph_pyx.pyx

@@ -529,7 +529,7 @@ def length_and_string_from_graph6(s):
     else:  # only first byte is N
         o = ord(s[0])
         if o > 126 or o < 63:
-            raise RuntimeError("the string seems corrupt: valid characters are \n" + ''.join(chr(i) for i in xrange(63, 127)))
+            raise RuntimeError("the string seems corrupt: valid characters are \n" + ''.join(chr(i) for i in range(63, 127)))
         n = o - 63
         s = s[1:]
     return n, s
@@ -568,7 +568,7 @@ def binary_string_from_graph6(s, n):
     for i in range(len(s)):
         o = ord(s[i])
         if o > 126 or o < 63:
-            raise RuntimeError("the string seems corrupt: valid characters are \n" + ''.join(chr(i) for i in xrange(63, 127)))
+            raise RuntimeError("the string seems corrupt: valid characters are \n" + ''.join(chr(i) for i in range(63, 127)))
         a = int_to_binary_string(o - 63)
         l.append('0'*(6 - len(a)) + a)
     m = "".join(l)
@@ -606,7 +606,7 @@ def binary_string_from_dig6(s, n):
     for i in range(len(s)):
         o = ord(s[i])
         if o > 126 or o < 63:
-            raise RuntimeError("the string seems corrupt: valid characters are \n" + ''.join(chr(i) for i in xrange(63, 127)))
+            raise RuntimeError("the string seems corrupt: valid characters are \n" + ''.join(chr(i) for i in range(63, 127)))
         a = int_to_binary_string(o - 63)
         l.append('0'*(6 - len(a)) + a)
     m = "".join(l)
@@ -862,14 +862,14 @@ cdef class SubgraphSearch:
 
         # line_h_out[i] represents the adjacency sequence of vertex i
         # in h relative to vertices 0, 1, ..., i-1
-        for i in xrange(self.nh):
+        for i in range(self.nh):
             self.line_h_out[i] = self.line_h_out[0] + i*self.nh
             self.h.adjacency_sequence_out(i, self.vertices, i, self.line_h_out[i])
 
         # Similarly in the opposite direction (only useful if the
         # graphs are directed)
         if self.directed:
-            for i in xrange(self.nh):
+            for i in range(self.nh):
                 self.line_h_in[i] = self.line_h_in[0] + i*self.nh
                 self.h.adjacency_sequence_in(i, self.vertices, i, self.line_h_in[i])
 
@@ -935,7 +935,7 @@ cdef class SubgraphSearch:
                 if self.active == self.nh-1:
                     sig_off()
                     return [self.g_vertices[self.stack[l]]
-                            for l in xrange(self.nh)]
+                            for l in range(self.nh)]
 
                 # We are still missing several vertices ...
                 else:

src/sage/libs/ntl/ntl_GF2X_linkage.pxi

@@ -180,7 +180,7 @@ cdef inline int celement_cmp(GF2X_c *a, GF2X_c *b, long parent) except -2:
     elif diff < 0:
         return -1
     else:
-        for i in xrange(GF2X_NumBits(a[0])-1, -1, -1):
+        for i in range(GF2X_NumBits(a[0])-1, -1, -1):
             ca = GF2_conv_to_long(GF2X_coeff(a[0], i))
             cb = GF2_conv_to_long(GF2X_coeff(b[0], i))
             if ca < cb:

src/sage/libs/ntl/ntl_mat_GF2E.pyx

@@ -726,27 +726,27 @@ cdef class ntl_mat_GF2E():
 
         if not nonzero:
             if _density == 1.0:
-                for i in xrange(self.x.NumRows()):
-                    for j in xrange(self.x.NumCols()):
+                for i in range(self.x.NumRows()):
+                    for j in range(self.x.NumCols()):
                         tmp = GF2E_random()
                         mat_GF2E_setitem(&self.x, i, j, &tmp)
             else:
-                for i in xrange(self.x.NumRows()):
-                    for j in xrange(self.x.NumCols()):
+                for i in range(self.x.NumRows()):
+                    for j in range(self.x.NumCols()):
                         if rstate.c_rand_double() <= _density:
                             tmp = GF2E_random()
                             mat_GF2E_setitem(&self.x, i, j, &tmp)
         else:
             if _density == 1.0:
-                for i in xrange(self.x.NumRows()):
-                    for j in xrange(self.x.NumCols()):
+                for i in range(self.x.NumRows()):
+                    for j in range(self.x.NumCols()):
                         tmp = GF2E_random()
                         while GF2E_IsZero(tmp):
                             tmp = GF2E_random()
                         mat_GF2E_setitem(&self.x, i, j, &tmp)
             else:
-                for i in xrange(self.x.NumRows()):
-                    for j in xrange(self.x.NumCols()):
+                for i in range(self.x.NumRows()):
+                    for j in range(self.x.NumCols()):
                         if rstate.c_rand_double() <= _density:
                             tmp = GF2E_random()
                             while GF2E_IsZero(tmp):

src/sage/matrix/matrix0.pyx

@@ -3760,7 +3760,7 @@ cdef class Matrix(sage.structure.element.Matrix):
                 else:
                     L.extend( L_prime )
         if return_diag:
-            return [d[i] for i in xrange(self._nrows)]
+            return [d[i] for i in range(self._nrows)]
         else:
             return True
 
@@ -4685,7 +4685,7 @@ cdef class Matrix(sage.structure.element.Matrix):
 
         X = set(self.pivots())
         np = []
-        for j in xrange(self.ncols()):
+        for j in range(self.ncols()):
             if j not in X:
                 np.append(j)
         np = tuple(np)
@@ -5073,7 +5073,7 @@ cdef class Matrix(sage.structure.element.Matrix):
             raise ArithmeticError("number of rows of matrix must equal degree of vector")
         cdef Py_ssize_t i
         return sum([v[i] * self.row(i, from_list=True)
-                    for i in xrange(self._nrows)], M(0))
+                    for i in range(self._nrows)], M(0))
 
     cdef _matrix_times_vector_(self, Vector v):
         """
@@ -5107,7 +5107,7 @@ cdef class Matrix(sage.structure.element.Matrix):
             raise ArithmeticError("number of columns of matrix must equal degree of vector")
         cdef Py_ssize_t i
         return sum([self.column(i, from_list=True) * v[i]
-                    for i in xrange(self._ncols)], M(0))
+                    for i in range(self._ncols)], M(0))
 
     def iterates(self, v, n, rows=True):
         r"""

src/sage/matrix/matrix2.pyx

@@ -3171,24 +3171,24 @@ cdef class Matrix(Matrix1):
         A = [R.zero()] * n
 
         F[0] = - M.get_unsafe(0, 0)
-        for t in xrange(1,n):
+        for t in range(1,n):
 
             # Set a(1, t) to be M(<=t, t)
             #
-            for i in xrange(t+1):
+            for i in range(t+1):
                 a.set_unsafe(0, i, M.get_unsafe(i, t))
 
             # Set A[1, t] to be the (t)th entry in a[1, t]
             #
             A[0] = M.get_unsafe(t, t)
 
-            for p in xrange(1, t):
+            for p in range(1, t):
 
                 # Set a(p, t) to the product of M[<=t, <=t] * a(p-1, t)
                 #
-                for i in xrange(t+1):
+                for i in range(t+1):
                     s = R.zero()
-                    for j in xrange(t+1):
+                    for j in range(t+1):
                         s = s + M.get_unsafe(i, j) * a.get_unsafe(p-1, j)
                     a.set_unsafe(p, i, s)
 
@@ -3199,13 +3199,13 @@ cdef class Matrix(Matrix1):
             # Set A[t, t] to be M[t, <=t] * a(p-1, t)
             #
             s = R.zero()
-            for j in xrange(t+1):
+            for j in range(t+1):
                 s = s + M.get_unsafe(t, j) * a.get_unsafe(t-1, j)
             A[t] = s
 
-            for p in xrange(t+1):
+            for p in range(t+1):
                 s = F[p]
-                for k in xrange(p):
+                for k in range(p):
                     s = s - A[k] * F[p-k-1]
                 F[p] = s - A[p]
 
@@ -6690,7 +6690,7 @@ cdef class Matrix(Matrix1):
             warn("Using generic algorithm for an inexact ring, which will probably give incorrect results due to numerical precision issues.")
 
         if not extend:
-            return Sequence(r for r,m in self.charpoly().roots() for _ in xrange(m))
+            return Sequence(r for r,m in self.charpoly().roots() for _ in range(m))
 
         # now we need to find a natural algebraic closure for the base ring
         K = self.base_ring()
@@ -11329,7 +11329,7 @@ cdef class Matrix(Matrix1):
                     C = B*C
                     ranks.append(C.rank())
                     i += 1
-                diagram = [ranks[i]-ranks[i+1] for i in xrange(len(ranks)-1)]
+                diagram = [ranks[i]-ranks[i+1] for i in range(len(ranks)-1)]
                 blocks.extend([(eval, i)
                                for i in Partition(diagram).conjugate()])
 
@@ -15474,7 +15474,7 @@ cdef class Matrix(Matrix1):
         """
         d = self.smith_form(transformation=False)
         r = min(self.nrows(), self.ncols())
-        return [d[i,i] for i in xrange(r)]
+        return [d[i,i] for i in range(r)]
 
     def smith_form(self, transformation=True, integral=None, exact=True):
         r"""
@@ -16005,7 +16005,7 @@ cdef class Matrix(Matrix1):
 
 
         try:
-            for i in xrange(1, len(pivs)):
+            for i in range(1, len(pivs)):
                 y = a[i][pivs[i]]
                 I = ideal_or_fractional(R, y)
                 s = a[0][pivs[i]]
@@ -17747,7 +17747,7 @@ def _smith_diag(d, transformation=True):
         right = d.new_matrix(d.ncols(), d.ncols(), 1)
     else:
         left = right = None
-    for i in xrange(n):
+    for i in range(n):
         I = ideal_or_fractional(R, dp[i,i])
 
         if I == ideal_or_fractional(R, 1):
@@ -17757,7 +17757,7 @@ def _smith_diag(d, transformation=True):
                 dp[i,i] = R(1)
             continue
 
-        for j in xrange(i+1,n):
+        for j in range(i+1,n):
             if dp[j,j] not in I:
                 t = ideal_or_fractional(R, [dp[i,i], dp[j,j]]).gens_reduced()
                 if len(t) > 1:
@@ -17842,7 +17842,7 @@ def _generic_clear_column(m):
     # is invertible over R
 
     I = ideal_or_fractional(R, a[0, 0]) # need to make sure we change this when a[0,0] changes
-    for k in xrange(1, a.nrows()):
+    for k in range(1, a.nrows()):
         if a[k,0] not in I:
             try:
                 v = ideal_or_fractional(R, a[0,0], a[k,0]).gens_reduced()
@@ -17889,7 +17889,7 @@ def _generic_clear_column(m):
                 raise ArithmeticError
 
     # now everything in column 0 is divisible by the pivot
-    for i in xrange(1,a.nrows()):
+    for i in range(1,a.nrows()):
         s = R( a[i, 0]/a[0, 0])
         a.add_multiple_of_row(i, 0, -s )
         left_mat.add_multiple_of_row(i, 0, -s)
@@ -17942,7 +17942,7 @@ def _smith_onestep(m):
 
     # test if everything to the right of the pivot in row 0 is good as well
     isdone = True
-    for jj in xrange(j+1, a.ncols()):
+    for jj in range(j+1, a.ncols()):
         if a[0,jj] != 0:
             isdone = False
 

src/sage/matrix/matrix_integer_dense.pyx

@@ -2454,10 +2454,10 @@ cdef class Matrix_integer_dense(Matrix_dense):
 
            :meth:`elementary_divisors`
         """
-        X = self.matrix_space()([self[i,j] for i in xrange(self._nrows-1,-1,-1) for j in xrange(self._ncols-1,-1,-1)])
+        X = self.matrix_space()([self[i,j] for i in range(self._nrows-1,-1,-1) for j in range(self._ncols-1,-1,-1)])
         v = X.__pari__().matsnf(1).sage()
         # need to reverse order of rows of U, columns of V, and both of D.
-        D = self.matrix_space()([v[2][i,j] for i in xrange(self._nrows-1,-1,-1) for j in xrange(self._ncols-1,-1,-1)])
+        D = self.matrix_space()([v[2][i,j] for i in range(self._nrows-1,-1,-1) for j in range(self._ncols-1,-1,-1)])
 
         if not transformation:
             return D
@@ -2471,13 +2471,13 @@ cdef class Matrix_integer_dense(Matrix_dense):
             # silly special cases for matrices with 0 columns (PARI has a unique empty matrix)
             U = self.matrix_space(ncols = self._nrows)(1)
         else:
-            U = self.matrix_space(ncols = self._nrows)([v[0][i,j] for i in xrange(self._nrows-1,-1,-1) for j in xrange(self._nrows-1,-1,-1)])
+            U = self.matrix_space(ncols = self._nrows)([v[0][i,j] for i in range(self._nrows-1,-1,-1) for j in range(self._nrows-1,-1,-1)])
 
         if self._nrows == 0:
             # silly special cases for matrices with 0 rows (PARI has a unique empty matrix)
             V = self.matrix_space(nrows = self._ncols)(1)
         else:
-            V = self.matrix_space(nrows = self._ncols)([v[1][i,j] for i in xrange(self._ncols-1,-1,-1) for j in xrange(self._ncols-1,-1,-1)])
+            V = self.matrix_space(nrows = self._ncols)([v[1][i,j] for i in range(self._ncols-1,-1,-1) for j in range(self._ncols-1,-1,-1)])
 
         return D, U, V
 
@@ -3310,7 +3310,7 @@ cdef class Matrix_integer_dense(Matrix_dense):
 
         #For any $i<d$, we have $\delta |b_i^*|^2 <= |b_{i+1}^* + mu_{i+1, i} b_i^* |^2$
         norms = [G[i].norm()**2 for i in range(len(G))]
-        for i in xrange(1,self.nrows()):
+        for i in range(1,self.nrows()):
             if norms[i] < (delta - mu[i,i-1]**2) * norms[i-1]:
                 return False
         return True

src/sage/matrix/matrix_integer_sparse.pyx

@@ -348,7 +348,7 @@ cdef class Matrix_integer_sparse(Matrix_sparse):
             if copy:
                 return list(x)
             return x
-        nzc = [[] for _ in xrange(self._ncols)]
+        nzc = [[] for _ in range(self._ncols)]
         cdef Py_ssize_t i, j
         for i from 0 <= i < self._nrows:
             for j from 0 <= j < self._matrix[i].num_nonzero: