noisegen

100 10-point wide steps with random amplitudes of normal distribution of mean 1 and standard deviation 0.7:

u = grand(1,100,"nor",1,0.7) .*. ones(1,10);
clf, plot(u);

40 15-point wide steps with random amplitudes of uniform distribution in [1 3], with initial level 0.5 and final level hold:

width = 15;
u = grand(1,40, "unf", 1, 3) .*. ones(1,width);
u = [ones(1,8*width)*0.5, u, ones(1,5*width)*u($)];
clf, plot(u);