Adding a row to the end of a matrix

A MWE could help. As this works:

julia> a = rand(3,3); b = rand(3,3)
3×3 Array{Float64,2}:
 0.985678  0.725839  0.162454
 0.235461  0.789938  0.304215
 0.303247  0.792388  0.332765

julia> [a;b[1,:]']
4×3 Array{Float64,2}:
 0.196151  0.294524   0.332187
 0.615515  0.0402781  0.0076374
 0.330384  0.841746   0.0751668
 0.985678  0.725839   0.162454