Add IsGenericMatrixRep matrix object type

benchmark/matobj/bench-matelm-access.g

@@ -136,17 +136,23 @@ RunMatTest := function(desc, m)
     TestWritingMatrix(m);
 end;
 
-m:=IdentityMat(10);;
-RunMatTest("integer matrix", m);
+m:=IdentityMat(10,GF(257));;    # plain list of plain lists
+RunMatTest("GF(257) plist-of-plist matrix", m);
 
-m:=IdentityMat(10,GF(2));;
+m:=IdentityMatrix(GF(257), 10); # IsPlistMatrixRep
+RunMatTest("GF(257) IsPlistMatrixRep", m);
+
+m:=IdentityMatrix(GF(257), 10); # IsGenericMatrixRep
+RunMatTest("GF(257) IsGenericMatrixRep", m);
+
+m:=IdentityMat(10,GF(2));;      # plain list of IsGF2VectorRep
 RunMatTest("GF(2) rowlist", m);
 
-m:=IdentityMat(10,GF(2));; ConvertToMatrixRep(m);;
+m:=IdentityMatrix(GF(2), 10);   # IsGF2MatrixRep
 RunMatTest("GF(2) compressed matrix", m);
 
-m:=IdentityMat(10,GF(7));;
+m:=IdentityMat(10,GF(7));;      # plain list of Is8BitVectorRep
 RunMatTest("GF(7) rowlist", m);
 
-m:=IdentityMat(10,GF(7));; ConvertToMatrixRep(m);;
+m:=IdentityMatrix(GF(7), 10);   # Is8BitMatrixRep
 RunMatTest("GF(7) compressed matrix", m);

benchmark/matobj/bench-matobj-creation.g

@@ -91,18 +91,23 @@ RunMatTest := function(desc, ring)
     TestCreatingMatrix(ring);
 end;
 
-RunMatTest("GF(2)", GF(2));
-RunMatTest("Rationals", Rationals);
-
 RunMatObjTest := function(desc, filter, ring)
     Print("\n");
     PrintBoxed(Concatenation("Testing ", desc));
     TestCreatingMatrixObj(filter, ring);
 end;
 
-RunMatObjTest("GF(2) IsPlistMatrixRep", IsPlistMatrixRep, GF(2));
+RunMatTest("GF(257)", GF(257));
+RunMatObjTest("GF(257) IsPlistMatrixRep", IsPlistMatrixRep, GF(257));
+RunMatObjTest("GF(257) IsGenericMatrixRep", IsGenericMatrixRep, GF(257));
+
+RunMatTest("Integers", Integers);
 RunMatObjTest("integer IsPlistMatrixRep", IsPlistMatrixRep, Integers);
+RunMatObjTest("integer IsGenericMatrixRep", IsGenericMatrixRep, Integers);
+
+RunMatTest("Rationals", Rationals);
 RunMatObjTest("rational IsPlistMatrixRep", IsPlistMatrixRep, Rationals);
+RunMatObjTest("rational IsGenericMatrixRep", IsGenericMatrixRep, Rationals);
 
 # TODO: other reps
 # TODO: other compare with creating plist-of-plist

doc/ref/makedocreldata.g

@@ -119,6 +119,7 @@ GAPInfo.ManualDataRef:= rec(
     "../../lib/matobj2.gd",
     "../../lib/matobjnz.gd",
     "../../lib/matobjplist.gd",
+    #"../../lib/matobjgeneric.gd",  # TODO: enable this if we decide to keep IsGenericMatrixRep
     "../../lib/matrix.gd",
     "../../lib/meataxe.gi",
     "../../lib/memory.gd",

doc/ref/matobj.xml

@@ -374,6 +374,7 @@ described in this chapter is supported.
 <#Include Label="IsGF2MatrixRep">
 <#Include Label="Is8BitMatrixRep">
 <#Include Label="IsPlistMatrixRep">
+<!-- <#Include Label="IsGenericMatrixRep"> TODO: enable this if we decide to keep IsGenericMatrixRep -->
 <#Include Label="IsZmodnZMatrixRep">
 
 </Section>

lib/matobjgeneric.gd

@@ -0,0 +1,46 @@
+#############################################################################
+##
+##  This file is part of GAP, a system for computational discrete algebra.
+##
+##  SPDX-License-Identifier: GPL-2.0-or-later
+##
+##  Copyright of GAP belongs to its developers, whose names are too numerous
+##  to list here. Please refer to the COPYRIGHT file for details.
+##
+
+############################################################################
+#
+# Dense matrix objects backed by plain lists of plain row lists.
+#
+
+#############################################################################
+##
+##  <#GAPDoc Label="IsGenericMatrixRep">
+##  <ManSection>
+##  <Filt Name="IsGenericMatrixRep" Arg='obj' Type="Representation"/>
+##
+##  <Description>
+##  An object <A>obj</A> in <Ref Filt="IsGenericMatrixRep"/> describes
+##  a matrix object (see <Ref Filt="IsMatrixObj"/>) whose entries are stored
+##  as a dense plain list of dense plain row lists.
+##  <P/>
+##  This representation is optimized for efficient entry access via
+##  <M>M[i,j]</M>. Unlike <Ref Filt="IsPlistMatrixRep"/>, it is not a row
+##  list matrix, so direct row access via <M>M[i]</M> is not supported.
+##  </Description>
+##  </ManSection>
+##  <#/GAPDoc>
+##
+DeclareRepresentation( "IsGenericMatrixRep",
+        IsMatrixObj and IsPositionalObjectRep
+    and IsCopyable
+    and IsNoImmediateMethodsObject
+    and HasNumberRows and HasNumberColumns
+    and HasBaseDomain and HasOneOfBaseDomain and HasZeroOfBaseDomain,
+    [] );
+
+
+# Internal positions for IsGenericMatrixRep:
+BindConstant( "FBDPOS", 1 );   # BaseDomain
+BindConstant( "FCOLSPOS", 2 ); # NumberColumns
+BindConstant( "FROWSPOS", 3 ); # "rows" as a plist-of-plists