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: reinit_SD_ENO2.m
    path of file: ./repos/Active-Contour-Model-Matlab/Narrow band
    
    the code of the file until where you have to start completion: function [phi] = reinit_SD_ENO2(phi, dx, dy, alpha, iterations)
%该方法见文件夹中的PPT"Level Set方法及其在图像图形中的应用"
% function [phi] = reinit_SD(phi, dx, dy, alpha, accuracy, iterations)
%重新初始化phi为符号距离函数
% Reinitializes phi into a signed distance function while preserving
% the zero level set (the interface or the curve).
%
% dx and dy are the resolution of the grid at x and y dimensions.
% alpha is a constant for calculating the euler step (dt). Should
% be between 0 and 1. 0.5 is quite safe whereas 0.9 can be risky.

    
function [phi] = reinit_SD_ENO2(phi, dx, dy, alpha, iterations)
%该方法见文件夹中的PPT"Level Set方法及其在图像图形中的应用"
% function [phi] = reinit_SD(phi, dx, dy, alpha, accuracy, iterations)
%重新初始化phi为符号距离函数
% Reinitializes phi into a signed distance function while preserving
% the zero level set (the interface or the curve).
%
% dx and dy are the resolution of the grid at x and y dimensions.
% alpha is a constant for calculating the euler step (dt). Should
% be between 0 and 1. 0.5 is quite safe whereas 0.9 can be risky.
% iterations specifies the number of iterations before the function returns.
% accuracy is the order of accuracy of derivative calculation.
% Allowed values for accuracy are 'ENO1', 'ENO2', 'ENO3', 'WENO'. 
% These correspond to 1st, 2nd, 3rd and 5th order accurate schemes 
% for calculating the derivative of phi.
%alpha为重新初始化的时间步长
%
% Author: Baris Sumengen  sumengen@ece.ucsb.edu
% http://vision.ece.ucsb.edu/~sumengen/bwdist


init_normal = @init_normal_ENO2;
evolve_normal = @evolve_normal_ENO2;

S_phi_0 = phi./sqrt(phi.^2 + dx.^2);

Vn_ext = feval(init_normal, S_phi_0);
it=0;
t=0;
while(it < iterations)
	[delta_normal, H1_abs, H2_abs] = feval(evolve_normal, phi, dx, dy, Vn_ext);
%feval(' fun ',x)求由字符串' fun '给定的函数值，其输入参量是变量x。即feval(' fun ',x)等价于求fun(x)值。

	dt = get_dt_normal(alpha, dx, dy, H1_abs, H2_abs);
	phi = phi + dt*(S_phi_0 - delta_normal);
	it = it+1;
	t = t+dt;
end