function out = triw(t,tau)
%  This function is the triangle function symmetric
%  about 0 of width 2*TAU and maximum height 1/TAU:
%
%   sig = vt(t, tau), where SIG and T are vectors of the same dimension.
%
%   elements of SIG are either 0 or (1/TAU)*(1-abs(T)/TAU) corresponding
%   to elements of d whose absolute values are greater than TAU and those
%   that are less than or equal to TAU, respectively.
%
%
%        written by Kevin D. Donohue  2/93
%
out = zeros(size(t));                       %  Initialize output vector
                                            %   with zeros.
elm_1 = find((t-tau <= 0) & (t+tau >=0));   %  Find t-axis values for nonzero range
out(elm_1) = (1/tau)*(1-abs(t(elm_1)/tau)); %  Plug into triange function.