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: read_ply.m
    path of file: ./repos/u-shape3D/software/extern
    
    the code of the file until where you have to start completion: function [vertex,face,d,c] = read_ply(filename)

% read_ply - read data from PLY file.
%
%   [vertex,face] = read_ply(filename);
%
%   'vertex' is a 'nb.vert x 3' array specifying the position of the vertices.
%   'face' is a 'nb.face x 3' array specifying the connectivity of the mesh.
%
%
%   Copyright (c) 2003 Gabriel Peyr?
%
% Copyright (C) 2024, Danuser Lab - UTSouthwestern 
%
% This file is part of Morphology3DPackage.
% 
% Morphology3DPackage is free software: you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by
% the Free Software Foundation, either version 3 of the License, or
% (at your option) any later version.
% 
% Morphology3DPackage is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
% GNU General Public License for more details.
% 
% You should have received a copy of the GNU
    
function [Elements,varargout] = plyread(Path,Str)
%PLYREAD   Read a PLY 3D data file.
%   [DATA,COMMENTS] = PLYREAD(FILENAME) reads a version 1.0 PLY file
%   FILENAME and returns a structure DATA.  The fields in this structure
%   are defined by the PLY header; each element type is a field and each
%   element property is a subfield.  If the file contains any comments,
%   they are returned in a cell string array COMMENTS.
%
%   [TRI,PTS] = PLYREAD(FILENAME,'tri') or
%   [TRI,PTS,DATA,COMMENTS] = PLYREAD(FILENAME,'tri') converts vertex
%   and face data into triangular connectivity and vertex arrays.  The
%   mesh can then be displayed using the TRISURF command.
%
%   Note: This function is slow for large mesh files (+50K faces),
%   especially when reading data with list type properties.
%
%   Example:
%   [Tri,Pts] = PLYREAD('cow.ply','tri');
%   trisurf(Tri,Pts(:,1),Pts(:,2),Pts(:,3)); 
%   colormap(gray); axis equal;
%
%   See also: PLYWRITE

% Pascal Getreuer 2004

[fid,Msg] = fopen(Path,'rt');	% open file in read text mode

if fid == -1, error(Msg); end