I have received the following error, and could not find any explanation for its meaning in Google search results.

```
ArgumentError: no outer repetition count may be negative; got (-1,)
Stacktrace:
[1] check
@ ./abstractarraymath.jl:318 [inlined]
[2] #repeat#1
@ ./abstractarraymath.jl:267 [inlined]
[3] repeat
@ ./abstractarraymath.jl:224 [inlined]
[4] buildQP_constrained!(ctrl::MPCController{OSQP.Model}, A::SubArray{Float64, 2, Matrix{Float64}, Tuple{Base.Slice{Base.OneTo{Int64}}, UnitRange{Int64}}, true}, B::SubArray{Float64, 2, Matrix{Float64}, Tuple{Base.Slice{Base.OneTo{Int64}}, UnitRange{Int64}}, true}, Q::Diagonal{Float64, Vector{Float64}}, R::Diagonal{Float64, Vector{Float64}}, Qf::Matrix{Float64}; kwargs::Base.Iterators.Pairs{Symbol, Real, Tuple{Symbol, Symbol}, NamedTuple{(:tol, :verbose), Tuple{Float64, Bool}}})
@ Main ./In[33]:36
[5] #buildQP!#36
@ ./In[11]:60 [inlined]
[6] top-level scope
@ In[34]:7
[7] eval
@ ./boot.jl:360 [inlined]
[8] include_string(mapexpr::typeof(REPL.softscope), mod::Module, code::String, filename::String)
@ Base ./loading.jl:1116
```

The code causing this problem is as shown:

```
ABI = hcat(A, B, -I)
AB = [sparse(hcat(A, B))]
E = blockdiag(sparse(B), repeat(AB, Nh-3)..., sparse(ABI)) # offblockdiag
# Add the identity matrices
for i = 1:Nh-1
E[N_r*(i-1).+(1:N_r), N_b2+N_ab2*(i-1).+(1:N_I)] .= -I(N_I)
end
```

According to the stacktrace, the error is occurring on the following line: `E = blockdiag(sparse(B), repeat(AB, Nh-3)..., sparse(ABI))`

The following information may also be useful:

typeof(A) = SubArray{Float64, 2, Matrix{Float64}, Tuple{Base.Slice{Base.OneTo{Int64}}, UnitRange{Int64}}, true}

typeof(B) = SubArray{Float64, 2, Matrix{Float64}, Tuple{Base.Slice{Base.OneTo{Int64}}, UnitRange{Int64}}, true}