sagemathgh-36595: Replace relative imports by absolute ones in `sage.…

…{coding,combinat,graphs}`

    
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URL: sagemath#36595
Reported by: Matthias Köppe
Reviewer(s): David Coudert

src/sage/coding/ag_code_decoders.pyx

@@ -66,8 +66,8 @@ from sage.rings.function_field.constructor import FunctionField
 from sage.modules.free_module_element import vector
 from sage.matrix.constructor import matrix
 
-from .encoder import Encoder
-from .decoder import Decoder, DecodingError
+from sage.coding.encoder import Encoder
+from sage.coding.decoder import Decoder, DecodingError
 
 from sage.modules.free_module_element cimport FreeModuleElement
 from sage.matrix.matrix cimport Matrix

src/sage/combinat/designs/designs_pyx.pyx

@@ -804,7 +804,7 @@ def is_quasi_difference_matrix(M,G,int k,int lmbda,int mu,int u,verbose=False):
         Column 1 contains 2 empty entries instead of the expected lambda.u=1.1=1
         False
     """
-    from .difference_family import group_law
+    from sage.combinat.designs.difference_family import group_law
 
     assert k>=2
     assert lmbda >=1

src/sage/combinat/designs/evenly_distributed_sets.pyx

@@ -310,7 +310,7 @@ cdef class EvenlyDistributedSetsBacktracker:
         xe = self.K.multiplicative_generator() ** (self.e)
         df = [[xe**j*b for b in B] for j in range((self.q-1)/(2*self.e))]
         if check:
-            from .difference_family import is_difference_family
+            from sage.combinat.designs.difference_family import is_difference_family
             if not is_difference_family(self.K, df, self.q, self.k, 1):
                 raise RuntimeError("a wrong evenly distributed set was "
                         "produced by the Sage library for the parameters:\n"

src/sage/combinat/designs/orthogonal_arrays_find_recursive.pyx

@@ -47,7 +47,7 @@ Functions
 """
 
 from sage.misc.cachefunc import cached_function
-from .orthogonal_arrays import orthogonal_array
+from sage.combinat.designs.orthogonal_arrays import orthogonal_array
 from sage.rings.integer cimport smallInteger
 from sage.arith.misc import prime_powers
 
@@ -153,7 +153,7 @@ cpdef find_product_decomposition(int k,int n) noexcept:
                   # faster to use that rather than calling the divisors function
             continue
         if is_available(k, n1) and is_available(k, n2):
-            from .orthogonal_arrays import wilson_construction
+            from sage.combinat.designs.orthogonal_arrays import wilson_construction
             return wilson_construction, (None,k,n1,n2,(),False)
     return False
 
@@ -203,7 +203,7 @@ cpdef find_wilson_decomposition_with_one_truncated_group(int k,int n) noexcept:
             is_available(k  ,m+1) and
             is_available(k+1,r  ) and
             is_available(k  ,u  )):
-            from .orthogonal_arrays import wilson_construction
+            from sage.combinat.designs.orthogonal_arrays import wilson_construction
             return wilson_construction, (None,k,r,m,(u,),False)
 
     return False
@@ -266,7 +266,7 @@ cpdef find_wilson_decomposition_with_two_truncated_groups(int k,int n) noexcept:
                 r2 = r1_p_r2-r1
                 if is_available(k,r2):
                     assert n == r*m+r1+r2
-                    from .orthogonal_arrays import wilson_construction
+                    from sage.combinat.designs.orthogonal_arrays import wilson_construction
                     return wilson_construction, (None,k,r,m,(r1,r2),False)
     return False
 
@@ -306,7 +306,7 @@ cpdef find_construction_3_3(int k,int n) noexcept:
 
             if (is_available(k+i, nn  ) and
                 is_available(k  , mm+i)):
-                from .orthogonal_arrays_build_recursive import construction_3_3
+                from sage.combinat.designs.orthogonal_arrays_build_recursive import construction_3_3
                 return construction_3_3, (k,nn,mm,i)
 
 cpdef find_construction_3_4(int k,int n) noexcept:
@@ -349,7 +349,7 @@ cpdef find_construction_3_4(int k,int n) noexcept:
                 if (is_available(k+r+1,nn) and
                     is_available(k    , s) and
                     (is_available(k,mm+r) or is_available(k,mm+r+1))):
-                    from .orthogonal_arrays_build_recursive import construction_3_4
+                    from sage.combinat.designs.orthogonal_arrays_build_recursive import construction_3_4
                     return construction_3_4, (k,nn,mm,r,s)
 
 cpdef find_construction_3_5(int k,int n) noexcept:
@@ -399,7 +399,7 @@ cpdef find_construction_3_5(int k,int n) noexcept:
                         (r==0 or is_available(k,r)) and
                         (s==0 or is_available(k,s)) and
                         (t==0 or is_available(k,t))):
-                        from .orthogonal_arrays_build_recursive import construction_3_5
+                        from sage.combinat.designs.orthogonal_arrays_build_recursive import construction_3_5
                         return construction_3_5, (k,nn,mm,r,s,t)
 
 cpdef find_construction_3_6(int k,int n) noexcept:
@@ -440,7 +440,7 @@ cpdef find_construction_3_6(int k,int n) noexcept:
 
             if (is_available(k+i,nn) and
                 smallInteger(nn).is_prime_power()):
-                from .orthogonal_arrays_build_recursive import construction_3_6
+                from sage.combinat.designs.orthogonal_arrays_build_recursive import construction_3_6
                 return construction_3_6, (k,nn,mm,i)
 
 cpdef find_q_x(int k,int n) noexcept:
@@ -492,7 +492,7 @@ cpdef find_q_x(int k,int n) noexcept:
             # is_available(k+1,q) and
             is_available(k, x+2 )            and
             smallInteger(q).is_prime_power()):
-            from .orthogonal_arrays_build_recursive import construction_q_x
+            from sage.combinat.designs.orthogonal_arrays_build_recursive import construction_q_x
             return construction_q_x, (k,q,x)
     return False
 
@@ -546,7 +546,7 @@ cpdef find_thwart_lemma_3_5(int k,int N) noexcept:
         sage: for k,n in kn:                                                     # not tested -- too long
         ....:     assert designs.orthogonal_array(k,n,existence=True) is True
     """
-    from .orthogonal_arrays_build_recursive import thwart_lemma_3_5
+    from sage.combinat.designs.orthogonal_arrays_build_recursive import thwart_lemma_3_5
     cdef int n,m,a,b,c,d,NN,na,nb,nc
 
     for n in prime_powers(k+2,N-2): # There must exist a OA(k+3,n) thus n>=k+2
@@ -661,7 +661,7 @@ cpdef find_thwart_lemma_4_1(int k,int n) noexcept:
                 not is_available(k,mm+4)):
                 continue
 
-            from .orthogonal_arrays_build_recursive import thwart_lemma_4_1
+            from sage.combinat.designs.orthogonal_arrays_build_recursive import thwart_lemma_4_1
             return thwart_lemma_4_1,(k,nn,mm)
 
     return False
@@ -706,7 +706,7 @@ cpdef find_three_factor_product(int k,int n) noexcept:
                 not is_available(k,n2) or
                 not is_available(k,n3)):
                 continue
-            from .orthogonal_arrays_build_recursive import three_factor_product
+            from sage.combinat.designs.orthogonal_arrays_build_recursive import three_factor_product
             return three_factor_product,(k-1,n1,n2,n3)
 
     return False
@@ -731,7 +731,7 @@ cpdef find_brouwer_separable_design(int k,int n) noexcept:
         sage: find_brouwer_separable_design(5,14)
         False
     """
-    from .orthogonal_arrays_build_recursive import brouwer_separable_design
+    from sage.combinat.designs.orthogonal_arrays_build_recursive import brouwer_separable_design
     cdef int q,x,baer_subplane_size, max_t, min_t, t,e1,e2,e3,e4
 
     for q in prime_powers(2,n):
@@ -945,13 +945,13 @@ cpdef find_brouwer_van_rees_with_one_truncated_column(int k,int n) noexcept:
 
             values = int_as_sum(remainder, available_multipliers, r)
             if values is not None:
-                from .orthogonal_arrays import wilson_construction
+                from sage.combinat.designs.orthogonal_arrays import wilson_construction
                 return (wilson_construction,
                         (None,k,r,m,[[(x,1) for x in values]]))
 
     return False
 
-from .designs_pyx cimport _OA_cache, _OA_cache_size
+from sage.combinat.designs.designs_pyx cimport _OA_cache, _OA_cache_size
 cdef int is_available(int k,int n) except -1:
     r"""
     Return whether Sage can build an OA(k,n)

src/sage/graphs/base/c_graph.pxd

@@ -6,7 +6,7 @@
 #**************************************************************************
 
 from sage.data_structures.bitset cimport bitset_t
-from .graph_backends cimport GenericGraphBackend
+from sage.graphs.base.graph_backends cimport GenericGraphBackend
 from libc.stdint cimport uint32_t
 
 cdef class CGraph:

src/sage/graphs/base/dense_graph.pxd

@@ -8,7 +8,7 @@
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
 
-from .c_graph cimport CGraph, CGraphBackend
+from sage.graphs.base.c_graph cimport CGraph, CGraphBackend
 from sage.data_structures.binary_matrix cimport binary_matrix_t
 
 cdef class DenseGraph(CGraph):

src/sage/graphs/base/graph_backends.pyx

@@ -57,7 +57,7 @@ Classes and methods
 # (at your option) any later version.
 #                  https://www.gnu.org/licenses/
 # ****************************************************************************
-from .c_graph cimport CGraphBackend
+from sage.graphs.base.c_graph cimport CGraphBackend
 
 
 cdef class GenericGraphBackend(SageObject):
@@ -722,9 +722,9 @@ cdef class GenericGraphBackend(SageObject):
             sage: loads(dumps(gi)) == gi
             True
         """
-        from .static_sparse_backend import StaticSparseBackend
-        from .sparse_graph import SparseGraphBackend
-        from .dense_graph import DenseGraphBackend
+        from sage.graphs.base.static_sparse_backend import StaticSparseBackend
+        from sage.graphs.base.sparse_graph import SparseGraphBackend
+        from sage.graphs.base.dense_graph import DenseGraphBackend
 
         # implementation, data_structure, multiedges, directed, loops
         if isinstance(self, CGraphBackend):

src/sage/graphs/base/sparse_graph.pxd

@@ -8,7 +8,7 @@
 #                  https://www.gnu.org/licenses/
 # ****************************************************************************
 
-from .c_graph cimport CGraph, CGraphBackend
+from sage.graphs.base.c_graph cimport CGraph, CGraphBackend
 cimport cython
 
 cdef struct SparseGraphLLNode:

src/sage/graphs/base/static_sparse_backend.pxd

@@ -1,7 +1,9 @@
-from .c_graph cimport CGraph, CGraphBackend
-from .static_sparse_graph cimport short_digraph, ushort
 from libc.stdint cimport uint64_t, uint32_t, INT32_MAX, UINT32_MAX
+
 from sage.data_structures.bitset cimport *
+from sage.graphs.base.c_graph cimport CGraph, CGraphBackend
+from sage.graphs.base.static_sparse_graph cimport short_digraph, ushort
+
 
 cdef class StaticSparseCGraph(CGraph):
     cdef short_digraph g
@@ -12,6 +14,7 @@ cdef class StaticSparseCGraph(CGraph):
     cpdef int out_degree(self, int u) except -1
     cpdef int in_degree(self, int u) except -1
 
+
 cdef class StaticSparseBackend(CGraphBackend):
     cdef int _order
     cdef bint _multiedges

src/sage/graphs/base/static_sparse_backend.pyx

@@ -43,7 +43,7 @@ from sage.graphs.base.static_sparse_graph cimport (init_short_digraph,
                                                    has_edge,
                                                    free_short_digraph,
                                                    edge_label)
-from .c_graph cimport CGraphBackend
+from sage.graphs.base.c_graph cimport CGraphBackend
 from sage.data_structures.bitset cimport FrozenBitset
 from libc.stdint cimport uint32_t
 from sage.data_structures.bitset_base cimport *

src/sage/graphs/base/static_sparse_graph.pyx

@@ -191,8 +191,8 @@ from memory_allocator cimport MemoryAllocator
 
 from sage.data_structures.bitset_base cimport *
 from sage.graphs.base.c_graph cimport CGraph
-from .static_sparse_backend cimport StaticSparseCGraph
-from .static_sparse_backend cimport StaticSparseBackend
+from sage.graphs.base.static_sparse_backend cimport StaticSparseCGraph
+from sage.graphs.base.static_sparse_backend cimport StaticSparseBackend
 
 
 cdef extern from "fenv.h":