Merged latest version of #20835 and fixed conflicts

src/doc/en/thematic_tutorials/coding_theory.rst

@@ -297,7 +297,7 @@ Let us see how one can explore this::
 
     sage: C = codes.GeneralizedReedSolomonCode(GF(59).list()[:40], 12, GF(59).list()[1:41])
     sage: C.encoders_available()
-    ['EvaluationPolynomial', 'EvaluationVector', 'Systematic', 'ParityCheck']
+    ['EvaluationPolynomial', 'EvaluationVector', 'Systematic']
     sage: C.decoders_available()
     ['Syndrome',
      'NearestNeighbor',

src/sage/coding/grs.py

@@ -38,9 +38,7 @@
 from sage.rings.integer import Integer
 from sage.misc.cachefunc import cached_method
 from copy import copy
-from linear_code import (AbstractLinearCode,
-                         LinearCodeSyndromeDecoder,
-                         LinearCodeNearestNeighborDecoder)
+from linear_code import AbstractLinearCode
 from encoder import Encoder
 from decoder import Decoder, DecodingError
 from sage.rings.arith import xgcd

src/sage/coding/hamming_code.py

@@ -22,9 +22,7 @@
 #*****************************************************************************
 
 from linear_code import (AbstractLinearCode,
-                         LinearCodeParityCheckEncoder,
-                         LinearCodeSyndromeDecoder,
-                         LinearCodeNearestNeighborDecoder)
+                         LinearCodeParityCheckEncoder)
 from sage.matrix.matrix_space import MatrixSpace
 from sage.schemes.projective.projective_space import ProjectiveSpace
 from sage.rings.integer import Integer
@@ -169,3 +167,8 @@ def minimum_distance(self):
             3
         """
         return 3
+
+
+####################### registration ###############################
+
+HammingCode._registered_encoders["ParityCheck"] = LinearCodeParityCheckEncoder

src/sage/coding/linear_code.py

@@ -806,7 +806,6 @@ def __init__(self, base_field, length, default_encoder_name, default_decoder_nam
         ### Add here any generic encoder/decoder ###
         #This allows any class which inherits from AbstractLinearCode
         #to use generic decoders/encoders
-        self._registered_encoders["ParityCheck"] = LinearCodeParityCheckEncoder
         self._registered_encoders["Systematic"] = LinearCodeSystematicEncoder
         self._registered_decoders["Syndrome"] = LinearCodeSyndromeDecoder
         self._registered_decoders["NearestNeighbor"] = LinearCodeNearestNeighborDecoder
@@ -1912,7 +1911,7 @@ def encode(self, word, encoder_name=None, **kwargs):
         It is possible to manually choose the encoder amongst the list of the available ones::
 
             sage: C.encoders_available()
-            ['GeneratorMatrix', 'Systematic', 'ParityCheck']
+            ['GeneratorMatrix', 'Systematic']
             sage: word = vector((0, 1, 1, 0))
             sage: C.encode(word, 'GeneratorMatrix')
             (1, 1, 0, 0, 1, 1, 0)
@@ -1965,7 +1964,7 @@ def encoder(self, encoder_name=None, **kwargs):
         an exception will be raised::
 
             sage: C.encoders_available()
-            ['GeneratorMatrix', 'Systematic', 'ParityCheck']
+            ['GeneratorMatrix', 'Systematic']
             sage: C.encoder('NonExistingEncoder')
             Traceback (most recent call last):
             ...
@@ -1994,10 +1993,9 @@ def encoders_available(self, classes=False):
             sage: G = Matrix(GF(2), [[1,1,1,0,0,0,0],[1,0,0,1,1,0,0],[0,1,0,1,0,1,0],[1,1,0,1,0,0,1]])
             sage: C = LinearCode(G)
             sage: C.encoders_available()
-            ['GeneratorMatrix', 'Systematic', 'ParityCheck']
+            ['GeneratorMatrix', 'Systematic']
             sage: C.encoders_available(True)
             {'GeneratorMatrix': <class 'sage.coding.linear_code.LinearCodeGeneratorMatrixEncoder'>,
-             'ParityCheck': <class 'sage.coding.linear_code.LinearCodeParityCheckEncoder'>,
              'Systematic': <class 'sage.coding.linear_code.LinearCodeSystematicEncoder'>}
         """
         if classes == True:
@@ -4006,6 +4004,8 @@ def __init__(self, code):
             sage: G = Matrix(GF(2), [[1,1,1,0,0,0,0],[1,0,0,1,1,0,0],[0,1,0,1,0,1,0],[1,1,0,1,0,0,1]])
             sage: C = LinearCode(G)
             sage: E = codes.encoders.LinearCodeParityCheckEncoder(C)
+            doctest:...: DeprecationWarning: LinearCodeParityCheckEncoder is now deprecated. Please use LinearCodeSystematicEncoder instead.
+            See http://trac.sagemath.org/20835 for details.
             sage: E
             Parity check matrix-based encoder for Linear code of length 7, dimension 4 over Finite Field of size 2
         """
@@ -4022,6 +4022,8 @@ def _repr_(self):
             sage: G = Matrix(GF(2), [[1,1,1,0,0,0,0],[1,0,0,1,1,0,0],[0,1,0,1,0,1,0],[1,1,0,1,0,0,1]])
             sage: C = LinearCode(G)
             sage: E = codes.encoders.LinearCodeParityCheckEncoder(C)
+            doctest:...: DeprecationWarning: LinearCodeParityCheckEncoder is now deprecated. Please use LinearCodeSystematicEncoder instead.
+            See http://trac.sagemath.org/20835 for details.
             sage: E
             Parity check matrix-based encoder for Linear code of length 7, dimension 4 over Finite Field of size 2
         """
@@ -4036,6 +4038,8 @@ def _latex_(self):
             sage: G = Matrix(GF(2), [[1,1,1,0,0,0,0],[1,0,0,1,1,0,0],[0,1,0,1,0,1,0],[1,1,0,1,0,0,1]])
             sage: C = LinearCode(G)
             sage: E = codes.encoders.LinearCodeParityCheckEncoder(C)
+            doctest:...: DeprecationWarning: LinearCodeParityCheckEncoder is now deprecated. Please use LinearCodeSystematicEncoder instead.
+            See http://trac.sagemath.org/20835 for details.
             sage: latex(E)
             \textnormal{Parity check matrix-based encoder for }[7, 4]\textnormal{ Linear code over }\Bold{F}_{2}
         """
@@ -4051,6 +4055,8 @@ def generator_matrix(self):
             sage: G = Matrix(GF(2), [[1,1,1,0,0,0,0],[1,0,0,1,1,0,0],[0,1,0,1,0,1,0],[1,1,0,1,0,0,1]])
             sage: C = LinearCode(G)
             sage: E = codes.encoders.LinearCodeParityCheckEncoder(C)
+            doctest:...: DeprecationWarning: LinearCodeParityCheckEncoder is now deprecated. Please use LinearCodeSystematicEncoder instead.
+            See http://trac.sagemath.org/20835 for details.
             sage: E.generator_matrix()
             [1 0 0 0 0 1 1]
             [0 1 0 0 1 0 1]
@@ -4164,7 +4170,7 @@ def generator_matrix(self):
         """
         C = self.code()
         if hasattr(self, "_use_pc_matrix"):
-            return C.parity_check_matrix()
+            return C.parity_check_matrix().right_kernel_matrix()
         else:
             self._use_pc_matrix = True
             M = C.generator_matrix()

src/sage/coding/punctured_code.py

@@ -16,9 +16,7 @@
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
 
-from linear_code import (AbstractLinearCode,
-                         LinearCodeSyndromeDecoder,
-                         LinearCodeNearestNeighborDecoder)
+from linear_code import AbstractLinearCode
 from encoder import Encoder
 from decoder import Decoder, DecodingError
 from sage.misc.cachefunc import cached_method