Fix NewZeroMatrix for IsGF2MatrixRep with zero rows

gap-system · Apr 15, 2021 · a0d16f0 · a0d16f0
1 parent 3611770
commit a0d16f0
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Showing 3 changed files with 10 additions and 12 deletions.
diff --git a/hpcgap/lib/vecmat.gi b/hpcgap/lib/vecmat.gi
@@ -2480,12 +2480,11 @@ InstallMethod( NewZeroMatrix, "for IsGF2MatrixRep, GF(2), and two ints",
     if rows = 0 then
         Error("IsGF2MatrixRep with zero rows not yet supported");
     fi;
-    m := 0*[1..rows];
-    m[1] := NewZeroVector(IsGF2VectorRep,f,cols);
-    for i in [2..rows] do
-        m[i] := ShallowCopy(m[1]);
+    m := EmptyPlist(rows);
+    for i in [1..rows] do
+        m[i] := ZERO_GF2VEC_2(cols);
     od;
-    ConvertToMatrixRep(m,2);
+    ConvertToMatrixRepNC(m,2);
     return m;
   end );
 

diff --git a/lib/vecmat.gi b/lib/vecmat.gi
@@ -2473,12 +2473,11 @@ InstallMethod( NewZeroMatrix, "for IsGF2MatrixRep, GF(2), and two ints",
     if rows = 0 then
         Error("IsGF2MatrixRep with zero rows not yet supported");
     fi;
-    m := 0*[1..rows];
-    m[1] := NewZeroVector(IsGF2VectorRep,f,cols);
-    for i in [2..rows] do
-        m[i] := ShallowCopy(m[1]);
+    m := EmptyPlist(rows);
+    for i in [1..rows] do
+        m[i] := ZERO_GF2VEC_2(cols);
     od;
-    ConvertToMatrixRep(m,2);
+    ConvertToMatrixRepNC(m,2);
     return m;
   end );
 

diff --git a/tst/testinstall/MatrixObj/ZeroMatrix.tst b/tst/testinstall/MatrixObj/ZeroMatrix.tst
@@ -7,7 +7,7 @@ gap> ReadGapRoot("tst/testinstall/MatrixObj/testmatobj.g");
 gap> TestZeroMatrix(IsGF2MatrixRep, GF(2), 2, 3);
 <a 2x3 matrix over GF2>
 gap> TestZeroMatrix(IsGF2MatrixRep, GF(2), 2, 0);
-Error, Assertion failure
+<a 2x0 matrix over GF2>
 gap> TestZeroMatrix(IsGF2MatrixRep, GF(2), 0, 3); # TODO
 Error, IsGF2MatrixRep with zero rows not yet supported
 
@@ -106,7 +106,7 @@ gap> ZeroMatrix(GF(2), 2, 3);
 gap> ZeroMatrix(GF(2), 0, 3);
 Error, IsGF2MatrixRep with zero rows not yet supported
 gap> ZeroMatrix(GF(2), 2, 0);
-[ <a GF2 vector of length 0>, <a GF2 vector of length 0> ]
+<a 2x0 matrix over GF2>
 
 #
 gap> ZeroMatrix(GF(3), 2, 3);