The conversion file of a Backpropagation Net must be used to convert ASCII characters (the net input) to an internal binary representation. The number of binary values that represent the ASCII characters can be changed freely, but has to be the same for each character.
The general structure of a conversion file is as follows:
In the first line:
Number of conversions
Each following line:
- At first position: The ASCII character
- and then: The binary representation (the length of this representation doesn't matter, but must be the same for each conversion)
Below you see the conversion file ascii2bin.cnv that is used in the BPN application. It contains 64 conversions (as can be seen in the first line) and each ASCII character is converted to 6 binary digits.
64
0000000
1000001
2000010
3000011
4000100
5000101
6000110
7000111
8001000
9001001
a001010
b001011
c001100
d001101
e001110
f001111
g010000
h010001
i010010
j010011
k010100
l010101
m010110
n010111
o011000
p011001
q011010
r011011
s011100
t011101
u011110
v011111
w100000
x100001
y100010
z100011
A100100
B100101
C100110
D100111
E101000
F101001
G101010
H101011
I101100
J101101
K101110
L101111
M110000
N110001
O110010
P110011
Q110100
R110101
S110110
T110111
U111000
V111001
W111010
X111011
Y111100
Z111101
?111110
?111111
Note: A conversion file must be read before you add neuron layers to the net, because the number of binary digits must already be available when a neuron layer is created.
