I noticed an odd thing when porting code from MATLAB, that this line makes a difference:

```
julia> gamma_gls_hat = gamma_gls_hat[:, :]
12×1 Matrix{Float64}
```

gamma_gls_hat as I calculated before this line was a 12-element Vector{Float64} and MATLAB doesn’t have that concept (at least originally, in MATLAB everything was a matrix, not sure if that changed, allowing vectors now).

So, as this has sometimes been important while translating (Julia is more strict), I added that line after my calculation, and was now checking if I could take it out.

I get the same 12 numbers in the matrix as in the vector (i.e. .== shows that, ==, or === doesn’t or shouldn’t), while none of the values in subsequent calculation are the same:

```
julia> (tmp*gamma_gls_hat) .== (tmp*gamma_gls_hat[:, :])
julia> (tmp*gamma_gls_hat) - (tmp*gamma_gls_hat[:, :])
5×1 Matrix{Float64}:
-4.336808689942018e-19
8.673617379884035e-19
-2.168404344971009e-19
2.168404344971009e-19
3.959879028413854e-20
julia> (tmp*gamma_gls_hat) ≈ (tmp*gamma_gls_hat[:, :]) # still:
true
julia> tmp
5×12 Matrix{Float64}:
julia> VERSION
v"1.6.0-DEV.1177"
```

I realize it’s only a bit off (and probably would be in all cases), caused by some optimization:

```
@edit (tmp*gamma_gls_hat[:, :]) # gets me to line 158:
# optimization for dispatching to BLAS, e.g. *(::Matrix{Float32}, ::Matrix{Float64})
# but avoiding the case *(::Matrix{<:BlasComplex}, ::Matrix{<:BlasReal})
# which is better handled by reinterpreting rather than promotion
function (*)(A::StridedMatrix{<:BlasReal}, B::StridedMatrix{<:BlasFloat})
```

vs.

```
@edit (tmp*gamma_gls_hat) # gets me to line 44:
function (*)(A::StridedMatrix{T}, x::StridedVector{S}) where {T<:BlasFloat,S<:Real}
```

I guess I shouldn’t strive for bit-identical, at least if I wanted, compared to MATLAB, I would need this extra line.