You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: fir2htw2.m
    path of file: ./repos/CanlabCore/CanlabCore/Data_processing_tools
    
    the code of the file until where you have to start completion: function [h,t,w,w_times,halfh, auc] = fir2htw2(b,varargin)
% Estimates height, time to peak, and width of FIR response
%
% :Usage:
% ::
%
%     [h,t,w,w_times,halfh, auc] = fir2htw2(b,[hconstraint],[doplot],[colors cell])
%

    
function [h,t,w,w_times,halfh, auc] = fir2htw2(b,varargin)
% Estimates height, time to peak, and width of FIR response
%
% :Usage:
% ::
%
%     [h,t,w,w_times,halfh, auc] = fir2htw2(b,[hconstraint],[doplot],[colors cell])
%
% :Inputs:
%
%   **b:**
%        beta/estimate series for hemodynamic response curve
%
%   hconstraint:**
%        max time in samples that can be considered the peak
%        (default = last sample)
%
%   doplot:**
%        flag for plot, 1/0
%
%   colors:**
%        cell vector of colors for plot
%
% ..
%    tor wager, 2/14/05
% ..
%
% minh = min height
%
% This version uses turning points (zero gradient) to find the largest
% "hump" in the data and the time it occurs.
%
% :Example:
% ::
%
%    hrf = spm_hrf(.5); hrf = hrf ./ max(hrf); hrf = hrf + .1 * randn(length(hrf), 1);
%    create_figure('hrf'); plot(hrf);
%    [h,t,w,w_times,halfh, auc] = fir2htw2(hrf, [], 1);
%

    if size(b,2) < length(b), b = b'; end