Cross Co Relation Xcorr ? urgent Help Please !

i have two file text file of 64KB each. one is the plaintext and other is encrypted text i want to calculate the xcorr between them i use the following code

x=fopen('d:/plaintext.txt')
w=fread(x)
char(w)
y=fopen('d:/encryptedtext.txt')
v=fread(y)
char(v)
[c,lags] = xcorr(w,v)
plot(c,lags)
xlabel('Time Shift')
ylabel('Correlation Coefficient')

It shows graph but i dnt understand the output how matlab is processing the output how will i come to knw that my answer is right

HELP NEEDED URGENTLY

[Walter Roberson]

If the encrypted text is correlated with the original then the encryption process was not a good one.

Answer 1

[nanren888]

Try plot(lags,c) ? Is this what you are looking for? c(lags) is a similarity measure. Otherwise, maybe give a little more info?

[Ali Umair]

Sir Thanks For the Reply But I wana ask that is there anything that must be include in the code to read and perform xcorr on 64kb file and how the result are interpreted how will i come to know that the answer is right ?,,what does lags means how its divide the time ?

Answer 2

[Walter Roberson]

This is not a resource for HELP NEEDED URGENTLY. If you need help urgently, then you should be hiring a consultant, such as http://www.mathworks.com/services/consulting/

Note: I am not a consultant, and I am not employed or contracted by MathWorks or any related company or organization in any capacity.

Disclaimer: I did receive a baseball-style hat from MathWorks once.