What's the difference between two command?

35 % Old help 36 %warning(['This calling syntax for ' mfilename ' will not be supported in the future.']) 37 %NYQUIST Nyquist frequency response for continuous-time linear systems. 38 % NYQUIST(A,B,C,D,IU) produces a Nyquist plot from the inputs 39 % IU to all the outputs of the system: 40 % . -1 41 % x = Ax + Bu G(s) = C(sI-A) B + D 42 % y = Cx + Du RE(w) = real(G(jw)), IM(w) = imag(G(jw)) 43 % 44 % The frequency range and number of points are chosen automatically. 45 % 46 % NYQUIST(NUM,DEN) produces the Nyquist plot for the polynomial 47 % transfer function G(s) = NUM(s)/DEN(s) where NUM and DEN contain 48 % the polynomial coefficients in descending powers of s. 49 % 50 % NYQUIST(A,B,C,D,IU,W) or NYQUIST(NUM,DEN,W) uses the user-supplied 51 % freq. vector W which must contain the frequencies, in radians/sec, 52 % at which the Nyquist response is to be evaluated. When invoked 53 % with left hand arguments, 54 % [RE,IM,W] = NYQUIST(A,B,C,D,...) 55 % [RE,IM,W] = NYQUIST(NUM,DEN,...) 56 % returns the frequency vector W and matrices RE and IM with as many 57 % columns as outputs and length(W) rows. No plot is drawn on the 58 % screen.