Signal Processing Cross Correlation

Greetings, I am new to signal processing. Would like a help to understand these codes I came across in file exchange. These codes were said to estimate spot spacing through image mean intensity projection.

yProfile = mean(a); ac = xcov(yProfile); %cross correlation p1 = diff(ac([1 1:end])); p2 = diff(ac([1:end end]));

I have read doc and help xcov but without sample/demo/tutorial I couldn't understand. Pls could someone explain it in simpler form and perhaps some exercise? And also what does [1 1:end] and [1: end end] means?

Thanks in advance guys :)

[Greg Heath]

To avoid confusion, use round parentheses instead of square brackets to denote matrix indices

(1 1:end) means row 1, all columns

(1:end 1) means all rows, column 1

[Greg Heath]

xcov is cross covariance, not cross correlation

xcorr is cross correlation

Check a statistics manual, text or wikipedia for the differences between

1. covariance and correlation

2. cross-covariance and cross-correlation

[Bella Sam]

Thanks a lot Greg! So sorry for this late reply. This helps me a lot in my work. I also go through signal processing books and matlab for beginners along the process. :)