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: icatb_gauss_smooth1D.m
    path of file: ./repos/bspm/thirdparty/MIALAB/GroupICATv4.0a/icatb/icatb_analysis_functions
    
    the code of the file until where you have to start completion: function data = icatb_gauss_smooth1D(data, FWHM)
% function data = gauss_smooth(data,FWHM)
% smooth in xy plane with a Gaussian Kernel
% replaces input image with smoothed image
%

    
function data = icatb_gauss_smooth1D(data, FWHM)
% function data = gauss_smooth(data,FWHM)
% smooth in xy plane with a Gaussian Kernel
% replaces input image with smoothed image
%
% Input:
% 1. data - data can be double or object of class complex_data
% and is of size nrows by ncols where each column indicates the
% observation.
% 2. FWHM - Smoothing factor
%
% Output:
% data - smoothed data

if (numel(data) == length(data))
    data = data(:);
end