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: lapcal.m
    path of file: ./repos/fieldtrip/private
    
    the code of the file until where you have to start completion: function [lap, edge] = lapcal(pnt, tri)

% LAPCAL computes the finite difference approximation to the surface laplacian
% matrix using a triangulation of the surface
%
% lap = lapcal(pnt, tri)
%
% where

    
function [lap, edge] = lapcal(pnt, tri)

% LAPCAL computes the finite difference approximation to the surface laplacian
% matrix using a triangulation of the surface
%
% lap = lapcal(pnt, tri)
%
% where
%   pnt   contains the positions of the vertices
%   tri   contains the triangle definition
%   lap   is the surface laplacian matrix
%
% See also LAPINT, LAPINTMAT, READ_TRI, SAVE_TRI

% For details see
%   T.F. Oostend