lsim, error message for single input system

[wahlquisty]

If I want to simulate a system with one input, for example

using ControlSystemsBase
A = ones(3,3);
B = ones(3,1);
C = ones(1,3);
D = 0;
model = ss(A,B,C,D);

t = LinRange(0,10,100) |> Vector
u = [ones(10,1); zeros(90,1)];
modeld = c2d(model,t[2]-t[1]);

and I want to call lsim(modeld,u,t). However, this results in the error message u must be of size (nu, length(t)) and the input u needs to be transposed to be a row vector lsim(modeld,u',t).
I suggest either adding the special case of nu == 1 or improve the error message to clarify.

[mzaffalon]

I have made a PR for the continuous case, #761 but it is worth updating it for the discrete one too.

[mzaffalon]

This can be closed now. With v1.5.1 I get

julia> lsim(modeld,u,t)
ERROR: u must have size (1, 100): got size (100, 1)

[baggepinnen]

awesome, thanks! :)