From c4bf93b77309015cc3f34517ac2773166501dd0d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lars=20G=C3=B6ttgens?= <lars.goettgens@rwth-aachen.de>
Date: Tue, 21 Nov 2023 09:24:16 +0100
Subject: [PATCH] Remove duplicate `*cat` implementations (#1467)

---
 src/Matrix.jl    |   2 +
 src/NemoStuff.jl | 123 -----------------------------------------------
 2 files changed, 2 insertions(+), 123 deletions(-)

diff --git a/src/Matrix.jl b/src/Matrix.jl
index 5220f7fd51..d8980ba050 100644
--- a/src/Matrix.jl
+++ b/src/Matrix.jl
@@ -6517,6 +6517,7 @@ function Base.vcat(A::MatrixElem{T}...) where T <: NCRingElement
   return _vcat(A)
 end
 
+# this leads to an ambiguity when calling `reduce(hcat, Union{}[])`, but we don't have a better solution right now
 Base.reduce(::typeof(vcat), A::AbstractVector{<:MatrixElem}) = _vcat(A)
 
 function _vcat(A)
@@ -6555,6 +6556,7 @@ function Base.hcat(A::MatrixElem{T}...) where T <: NCRingElement
   return _hcat(A)
 end
 
+# this leads to an ambiguity when calling `reduce(hcat, Union{}[])`, but we don't have a better solution right now
 Base.reduce(::typeof(hcat), A::AbstractVector{<:MatrixElem}) = _hcat(A)
 
 function _hcat(A)
diff --git a/src/NemoStuff.jl b/src/NemoStuff.jl
index a518f83d8c..17cd2cd497 100644
--- a/src/NemoStuff.jl
+++ b/src/NemoStuff.jl
@@ -172,129 +172,6 @@ function sub(M::Generic.Mat, rows::AbstractUnitRange{Int}, cols::AbstractUnitRan
     return z
 end
 
-################################################################################
-#
-#  Concatenation of matrices
-#
-################################################################################
-
-@doc raw"""
-    vcat(A::Vector{Mat}) -> Mat
-
-Forms a big matrix by vertically concatenating the matrices in $A$.
-All component matrices need to have the same number of columns.
-"""
-function Base.vcat(A::Vector{T}) where {S<:RingElem,T<:MatElem{S}}
-    if any(x -> ncols(x) != ncols(A[1]), A)
-        error("Matrices must have same number of columns")
-    end
-    M = zero_matrix(base_ring(A[1]), sum(nrows, A), ncols(A[1]))
-    s = 0
-    for i = A
-        for j = 1:nrows(i)
-            for k = 1:ncols(i)
-                M[s+j, k] = i[j, k]
-            end
-        end
-        s += nrows(i)
-    end
-    return M
-end
-
-function Base.hcat(A::Vector{T}) where {S<:RingElem,T<:MatElem{S}}
-    if any(x -> nrows(x) != nrows(A[1]), A)
-        error("Matrices must have same number of rows")
-    end
-    M = zero_matrix(base_ring(A[1]), nrows(A[1]), sum(ncols, A))
-    s = 0
-    for i = A
-        for j = 1:ncols(i)
-            for k = 1:nrows(i)
-                M[k, s+j] = i[k, j]
-            end
-        end
-        s += ncols(i)
-    end
-    return M
-end
-
-function Base.hcat(A::MatElem...)
-    r = nrows(A[1])
-    c = ncols(A[1])
-    R = base_ring(A[1])
-    for i = 2:length(A)
-        @assert nrows(A[i]) == r
-        @assert base_ring(A[i]) == R
-        c += ncols(A[i])
-    end
-    X = zero_matrix(R, r, c)
-    o = 1
-    for i = 1:length(A)
-        for j = 1:ncols(A[i])
-            X[:, o] = A[i][:, j]
-            o += 1
-        end
-    end
-    return X
-end
-
-function Base.cat(A::MatElem...; dims)
-    @assert dims == (1, 2) || isa(dims, Int)
-
-    if isa(dims, Int)
-        if dims == 1
-            return hcat(A...)
-        elseif dims == 2
-            return vcat(A...)
-        else
-            error("dims must be 1, 2, or (1,2)")
-        end
-    end
-
-    local X
-    for i = 1:length(A)
-        if i == 1
-            X = hcat(A[1], zero_matrix(base_ring(A[1]), nrows(A[1]), sum(Int[ncols(A[j]) for j = 2:length(A)])))
-        else
-            X = vcat(X, hcat(zero_matrix(base_ring(A[1]), nrows(A[i]), sum(ncols(A[j]) for j = 1:i-1)), A[i], zero_matrix(base_ring(A[1]), nrows(A[i]), sum(Int[ncols(A[j]) for j = i+1:length(A)]))))
-        end
-    end
-    return X
-end
-
-#= seems to be in AA now
-function Base.hvcat(rows::Tuple{Vararg{Int}}, A::MatElem...)
-  B = hcat([A[i] for i=1:rows[1]]...)
-  o = rows[1]
-  for j=2:length(rows)
-    C = hcat([A[i+o] for i=1:rows[j]]...)
-    o += rows[j]
-    B = vcat(B, C)
-  end
-  return B
-end
-=#
-
-function Base.vcat(A::MatElem...)
-    r = nrows(A[1])
-    c = ncols(A[1])
-    R = base_ring(A[1])
-    for i = 2:length(A)
-        @assert ncols(A[i]) == c
-        @assert base_ring(A[i]) == R
-        r += nrows(A[i])
-    end
-    X = zero_matrix(R, r, c)
-    o = 1
-    for i = 1:length(A)
-        for j = 1:nrows(A[i])
-            X[o, :] = A[i][j, :]
-            o += 1
-        end
-    end
-    return X
-end
-
 gens(L::SimpleNumField{T}) where {T} = [gen(L)]
 
 function gen(L::SimpleNumField{T}, i::Int) where {T}