How to solve the Logistic Delay differential equation with out using dde23, ddesd, ddensd, deval functions? Need to use for loop or if condition.... Please help

 %% Dx(t) = r*x(t)*(1-x(t-tau))
%% r=0.5
%% x(0)=0.85
%% If tau=0 
%% Dx(t) = r*x(t)*(1-x(t))
%% r=0.5
%% x(0)=0.85
%% We use Nonstandard finite difference scheme and obtain the code given below. 
close all
clear all
clc
N=100;
h=0.2;
r=0.5;
x(1)=0.85;
for n=2:h: N
x(n)=(1+h*r)*x(n-1)/(1+h*x(n-1))
end
plot (x)

Please write the code using tau function (Means delay factor)

Please donot use built in functions....

[Steven Lord]

The fact that you're asking not to use the built-in functions suggests to me that this is a homework assignment. If that's the case show us the full text of the assignment and what you've tried to do to solve the assignment and ask a specific question about where you're having difficulty and you may receive some guidance.

If this is not a homework assignment, why aren't you allowed to use the delay differential equation solvers included in MATLAB? Doing so probably would be easier and more robust than building your own.