Here's an example to illustrate my problem constructing a neural
network (NN) under Matlab.
When I plot the target value (X) and the NN output (Y), for a real
value of 0.7 the NN output is at worse between 0.68 and 0.73 (pretty
bad but it was just a test!).
If I use the NN weights to calculate the output value by hand, I get a
0.75, wich is impossible for 0.7!
So I must be wrong somewhere in the calculation of my output... The
network is a 2 inputs/3 hidden/1 output with Tangente sigmoide
activation for the hidden layer and linear activation for the output.
Here's the formula I used in Matlab:
1.1261*tansig(1.6589*0.6964+1.4776*0.6936+4.5965)
0.013796*tansig(2.6065*0.6964+ 4.3402 *0.6936+0.30321)
+1.2166*tansig( 0.88612*0.6964+0.11309 *0.6936+0.055821)+1.1116

The weights :
Weights to layer from input
[1.6589 1.4776;
2.6065 4.3402;
0.88612 0.11309]
Weights to layer
[1.1261 0.013796 1.2166]
Bias to layer 1
[4.5965;
0.30321;
0.055821]
Bias to layer 2
[1.1116]
The 2 example inputs used to calculate the output are :
0.6964
0.6936

Thanks for your help!
