add row/column vec to noteworthy difference

docs/src/man/differences.md

@@ -10,6 +10,7 @@ The rest of this page will list noteworthy differences between ControlSystems.jl
 - Functions [`bode`](@ref), [`nyquist`](@ref) etc. never produce a plot. Instead, see [`bodeplot`](@ref), [`nyquistplot`](@ref) etc.
 - In Julia, functionality is often split up into several different packages. You may therefore have to install and use additional packages in order to cover all your needs. See [Ecosystem](@ref) for a collection of control-related packages.
 - In Julia, `1` has a different type than `1.0`, and the types in ControlSystemsBase.jl respect the types chosen by the user. As an example, `tf(1, [1, 1])` is a transfer function with integer coefficients, while `tf(1.0, [1, 1])` will promote all coefficients to `Float64`.
+- Julia treats matrices and vectors as different types, in particular, column vectors and row vectors are not interchangeable. 
 - In Julia, code can often be differentiated using automatic differentiation. When using ControlSystems.jl, we recommend trying [ForwardDiff.jl](https://github.com/JuliaDiff/ForwardDiff.jl/) for AD. An example making use of this is available [here](https://github.com/JuliaControl/ControlExamples.jl/blob/master/autotuning.ipynb).
 - In Julia, the source code is often very readable. If you want to learn how a function is implemented, you may find the macros `@edit` or `@less` useful to locate the source code.
 - If you run into an issue (bug) with a Julia package, you can share this issue (bug report) on the package's github page and it will often be fixed promptly. To open an issue with ControlSystems.jl, [click here](https://github.com/JuliaControl/ControlSystems.jl/issues/new/choose). Thank you for helping out improving open-source software!

lib/ControlSystemsBase/src/timeresp.jl

@@ -125,7 +125,7 @@ plot(result, plotu=true, plotx=false)
 
 Continuous-time systems are simulated using an ODE solver if `u` is a function (requires using ControlSystems). If `u` is an array, the system is discretized (with `method=:zoh` by default) before simulation. For a lower-level inteface, see `?Simulator` and `?solve`
 
-`u` can be a function or a *matrix* of precalculated control signals and must have dimentions `(nu, length(t))`.
+`u` can be a function or a *matrix* of precalculated control signals and must have dimensions `(nu, length(t))`.
 If `u` is a function, then `u(x,i)` (for discrete systems) or `u(x,t)` (for continuos ones) is called to calculate the control signal at every iteration (time instance used by solver). This can be used to provide a control law such as state feedback `u(x,t) = -L*x` calculated by `lqr`.
 To simulate a unit step at `t=t₀`, use `(x,t)-> t ≥ t₀`, for a ramp, use `(x,t)-> t`, for a step at `t=5`, use (x,t)-> (t >= 5) etc.