Why the code is giving different results, every time I run it ???

clc;clear all;close all;

net = newff([-10 10],[4 1],{'tansig','purelin'});

p = [-10 -5 0 5 10];

t = [0 0 1 1 1];

y = sim(net,p);

e = t-y;

perf = mse(e);

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Why the result of the code is giving different results every time I run it.

[Jan]

clc;clear all;close all; is a brute cleaning. Especially clear all is not useful, but use clear variables to allow Matlab to keep the expensively parsed functions in the memory.

Answer 1

[Shashank Prasanna]

This is due to random setting of the initial weights and biases.

You can confirm that by setting the random seed each time and your results will be reproducible:

clc;clear all;close all;
rand('seed',0) % set random seed
net = newff([-10 10],[4 1],{'tansig','purelin'});
p = [-10 -5 0 5 10];
t = [0 0 1 1 1];
y = sim(net,p);
e = t-y;
perf = mse(e);

Answer 2

[Vito]

Each time occurs network initialization. That is initial IW installation. Usually it occurs in a random way. Therefore result, on an untrained network always the different.