fstep.m

控制系统计算机辅助设计——MATLAB语言与应用(源代码）

function [y,t] = fstep(w,f,iu)
%FSTEP Step response form frequency response (MIMO).
%        [y,t] = fstep(w,f,iu)
%            y = fstep(w,f,iu)
%
% Computes step response from frequency response.
% f is a MVFR matrix, iu is the input on which a unit
% step is applied.
% w is the frequency list, which must have (N/2)+1
% evenly spaced points on it. The first point should
% be 0. N should be a power of 2. w is most conveniently
% generated using function T2W.
%
% The output y is a matrix with as many columns as there are
% outputs, and N rows, each representing one time point.
%
% Optionally, t is the list of time points at which the step
% response is computed (it can also be generated by T2W).
%
% This function allows the step response of systems 
% containing time delays to be generated.
%
% See also: FIMPULSE

% J.M.Maciejowski, 1 June 1988. Revised 8 June and 3 December 1988, JMM.
% Copyright (c) 1988, by Cambridge Control Ltd.

[nout,nin] = fsize(w,f); 

[y,t] = fimpulse(w,f,iu);
y = [zeros(1,nout); cumsum(y)]*t(2); % Rough integration
[rows,cols] = size(y);
y = y(1:rows-1,:); % Remove last time point.