ffmat: remove undocumented RandomMatrix(field, dim, rank/s)

These function conflict with forthcoming changes in GAP, and since they
are undocumented, I'm just removing them in this commit.

See:

gap-system/gap#6232
#1158

Author: james-d-mitchell

gap/elements/ffmat.gi

@@ -69,43 +69,6 @@ function(field, n)
   return Matrix(field, xy);
 end);
 
-InstallMethod(RandomMatrixOp,
-"for a finite field, dimension, and list of ranks",
-[IsField and IsFinite, IsPosInt, IsList],
-function(R, n, ranks)
-  local z, rk, mat, zv, conj, j;
-
-  if ForAny(ranks, x -> (x < 0) or (x > n)) then
-    ErrorNoReturn("the list of ranks has to consist of numbers > 0 and < n");
-  fi;
-
-  z := Zero(R);
-  # Choose a matrix of given rank
-  rk := Random(ranks);
-  if rk = 0 then
-    return ZeroMatrix(R, n, n);
-  fi;
-  mat := Unpack(Random(GL(rk, R)));
-  # Extend it to n x n
-  zv := [1 .. n - rk] * z;
-  for j in [1 .. rk] do
-    Append(mat[j], zv);
-  od;
-  zv := [1 .. n] * z;
-  for j in [1 .. n - rk] do
-    Add(mat, zv);
-  od;
-  # Swirl around
-  # Is Permuting rows/columns enough?
-  conj := Random(GL(n, R));  # PermutationMat(Random(Sym(n)), n, R);
-  return Matrix(R, mat ^ conj);
-end);
-
-InstallMethod(RandomMatrixOp,
-"for a finite field, dimension, and pos int",
-[IsField and IsFinite, IsPosInt, IsPosInt],
-{R, n, rank} -> RandomMatrixOp(R, n, [rank]));
-
 #############################################################################
 # 2. Rows bases etc
 #############################################################################

gap/elements/semiringmat.gd

@@ -82,8 +82,6 @@ DeclareOperation("RandomMatrix",
 DeclareOperation("RandomMatrix",
                  [IsOperation, IsPosInt, IsInt, IsInt]);
 DeclareOperation("RandomMatrix", [IsSemiring, IsInt]);
-DeclareOperation("RandomMatrix", [IsSemiring, IsInt, IsPosInt]);
-DeclareOperation("RandomMatrix", [IsSemiring, IsInt, IsList]);
 
 DeclareConstructor("RandomMatrixCons", [IsMatrixOverSemiring,
                                         IsPosInt]);
@@ -95,9 +93,6 @@ DeclareConstructor("RandomMatrixCons", [IsMatrixOverSemiring,
                                         IsInt,
                                         IsInt]);
 DeclareOperation("RandomMatrixOp", [IsSemiring, IsPosInt]);
-DeclareOperation("RandomMatrixOp", [IsField and IsFinite, IsPosInt, IsList]);
-DeclareOperation("RandomMatrixOp", [IsField and IsFinite, IsZeroCyc, IsList]);
-DeclareOperation("RandomMatrixOp", [IsField and IsFinite, IsPosInt, IsPosInt]);
 
 DeclareAttribute("AsList", IsMatrixOverSemiring);
 DeclareOperation("AsMutableList", [IsMatrixOverSemiring]);

gap/elements/semiringmat.gi

@@ -307,23 +307,23 @@ function(semiring, dim)
   return RandomMatrixOp(semiring, dim);
 end);
 
-InstallMethod(RandomMatrix, "for a semiring, non-negative int, and pos int",
-[IsSemiring, IsInt, IsPosInt],
-function(semiring, dim, rank)
-  if dim < 0 then
-    TryNextMethod();
-  fi;
-  return RandomMatrixOp(semiring, dim, rank);
-end);
-
-InstallMethod(RandomMatrix, "for a semiring, non-negative int, and list",
-[IsSemiring, IsInt, IsList],
-function(semiring, dim, ranks)
-  if dim < 0 then
-    TryNextMethod();
-  fi;
-  return RandomMatrixOp(semiring, dim, ranks);
-end);
+# InstallMethod(RandomMatrix, "for a semiring, non-negative int, and pos int",
+# [IsSemiring, IsInt, IsPosInt],
+# function(semiring, dim, rank)
+#   if dim < 0 then
+#     TryNextMethod();
+#   fi;
+#   return RandomMatrixOp(semiring, dim, rank);
+# end);
+#
+# InstallMethod(RandomMatrix, "for a semiring, non-negative int, and list",
+# [IsSemiring, IsInt, IsList],
+# function(semiring, dim, ranks)
+#   if dim < 0 then
+#     TryNextMethod();
+#   fi;
+#   return RandomMatrixOp(semiring, dim, ranks);
+# end);
 
 InstallMethod(AsTransformation, "for a matrix over semiring",
 [IsMatrixOverSemiring],

gap/semigroups/semiffmat.gi

@@ -308,19 +308,17 @@ SEMIGROUPS_ProcessRandomArgsCons(IsMatrixOverFiniteFieldSemigroup, params));
 InstallMethod(RandomSemigroupCons,
 "for IsMatrixOverFiniteFieldSemigroup and list",
 [IsMatrixOverFiniteFieldSemigroup, IsList],
-function(_, params)  # params = [nrgens, dim, field, ranks]
+function(_, params)  # params = [nrgens, dim, field]
   return Semigroup(List([1 .. params[1]], i -> RandomMatrix(params[3],
-                                                            params[2],
-                                                            params[4])));
+                                                            params[2])));
 end);
 
 InstallMethod(RandomMonoidCons,
 "for IsMatrixOverFiniteFieldMonoid and list",
 [IsMatrixOverFiniteFieldMonoid, IsList],
-function(_, params)  # params = [nrgens, dim, field, ranks]
+function(_, params)  # params = [nrgens, dim, field]
   return Monoid(List([1 .. params[1]], i -> RandomMatrix(params[3],
-                                                         params[2],
-                                                         params[4])));
+                                                         params[2])));
 end);
 
 InstallMethod(RandomInverseSemigroupCons,

tst/standard/elements/ffmat.tst

@@ -87,20 +87,6 @@ gap> NrRows(x);
 gap> x := RandomMatrix(GF(8), 10);;
 gap> NrRows(x);
 10
-gap> x := RandomMatrix(GF(3), 3, [3]);;
-gap> Rank(x);
-3
-gap> x := RandomMatrix(GF(3), 10, [3 .. 8]);;
-gap> Rank(x) in [3 .. 8];
-true
-gap> x := RandomMatrix(GF(3), 5, [0]);
-[ [ 0*Z(3), 0*Z(3), 0*Z(3), 0*Z(3), 0*Z(3) ], 
-  [ 0*Z(3), 0*Z(3), 0*Z(3), 0*Z(3), 0*Z(3) ], 
-  [ 0*Z(3), 0*Z(3), 0*Z(3), 0*Z(3), 0*Z(3) ], 
-  [ 0*Z(3), 0*Z(3), 0*Z(3), 0*Z(3), 0*Z(3) ], 
-  [ 0*Z(3), 0*Z(3), 0*Z(3), 0*Z(3), 0*Z(3) ] ]
-gap> x := RandomMatrix(GF(3), 5, [1, -2, 1314]);
-Error, the list of ranks has to consist of numbers > 0 and < n
 
 # Test \ = , \< for row basis
 gap> mat := Matrix(GF(3 ^ 2),
@@ -217,13 +203,6 @@ gap> Display(mat);
   9  2  7  8 10
   .  3  8  9  1
 
-# Test RandomMatrix for finite field, dim, rank
-gap> x := RandomMatrix(GF(3), 3, 1);;
-gap> Rank(x);
-1
-gap> Rank(TransposedMat(x));
-1
-
 # Test MatrixNC
 gap> x := Matrix(GF(3), [[Z(3) ^ 0, 0 * Z(3), Z(3)], [Z(3), 0 * Z(3), Z(3)],
 > [Z(3) ^ 0, Z(3) ^ 0, Z(3)]]);;
@@ -234,17 +213,6 @@ gap> z := Matrix(Unpack(x), y);
 gap> z = x;
 true
 
-# Test RandomMatrix
-gap> RandomMatrix(GF(11), 0, []);
-Error, no method found! For debugging hints type ?Recovery from NoMethodFound
-Error, no 1st choice method found for `RandomMatrixOp' on 3 arguments
-gap> RandomMatrix(GF(11), 0, [0]);
-Error, no method found! For debugging hints type ?Recovery from NoMethodFound
-Error, no 1st choice method found for `RandomMatrixOp' on 3 arguments
-gap> RandomMatrix(GF(11), 0, [1]);
-Error, no method found! For debugging hints type ?Recovery from NoMethodFound
-Error, no 1st choice method found for `RandomMatrixOp' on 3 arguments
-
 # Test AsList for IsPlistMatrixRep 
 gap> S := Semigroup(Transformation([2, 3, 1]));;
 gap> IsGroupAsSemigroup(S);

tst/standard/elements/semiringmat.tst

@@ -499,14 +499,6 @@ gap> mat := Matrix(GF(3), [[Z(3)]]);
 gap> Matrix(GF(3), mat);
 [ [ Z(3) ] ]
 
-# Test RandomMatrix for a finite field
-gap> mat := RandomMatrix(GF(3), 3, 2);;
-gap> Rank(mat);
-2
-gap> mat := RandomMatrix(GF(3), 3, [2, 3]);;
-gap> Rank(mat) in [2, 3];
-true
-
 # Test OneImmutable, fails
 gap> coll := [Matrix(IsNTPMatrix, [[2, 2], [0, 1]], 10, 10),
 >             Matrix(IsNTPMatrix, [[2, 2], [0, 1]], 10, 9)];;
@@ -589,12 +581,6 @@ IO_Error
 gap> RandomMatrix(Integers, -1);
 Error, no method found! For debugging hints type ?Recovery from NoMethodFound
 Error, no 2nd choice method found for `RandomMatrix' on 2 arguments
-gap> RandomMatrix(Integers, -1, 2);
-Error, no method found! For debugging hints type ?Recovery from NoMethodFound
-Error, no 2nd choice method found for `RandomMatrix' on 3 arguments
-gap> RandomMatrix(Integers, -1, [2]);
-Error, no method found! For debugging hints type ?Recovery from NoMethodFound
-Error, no 2nd choice method found for `RandomMatrix' on 3 arguments
 
 #
 gap> SEMIGROUPS.StopTest();