HOW TO XOR NEGETIVE DECIMAL NUMBER?

My original image size 256*256. I have performed transformation, then i divided the matrix into 4*4 block, then i performed decomposition on each block...output of decomposition was P ans S matrix...i shuffled the elements of p..but now i want to perform xor with s. but my problem is i need to xor a key with s matrix which contain negetive decimal number .. but it showing me error ..

for i=1:16
    bi=xor(Dec2bin(smod(i)),Dec2bin(finalkey(i)));
    s1(i)= Binary2Dec(bi);
end

[James Tursa]

What are the variable types of smod and finalkey? Can you post a small subset of example data?

[Al Anher Provat]

Smod contains positive+negative double and final key contains decimal number actually.

Answer 1

[Walter Roberson]

for i=1:16
    S = dec2bin(typecast(double(smod(i)), 'uint8'), 8) - '0');
    F = dec2bin(typecast(double(finalkey(i)), 'uint8'), 8) - '0'));
    bi = xor(S, F);
    s1(i) = typecast(uint8(bin2dec(char(bi + '0'))), 'double');
end

[Walter Roberson]

This code assumes that the "negative decimal numbers" are not int64 or uint64

[sabitri]

It worked....Thanks @Walter Roberson

[Walter Roberson]

I have no idea what your Dec2Bin function is.

dec2bin has accepted a second parameter for at least the last 5 years.

[Walter Roberson]

Why? Why are you not using dec2bin() ?