RunXCorr Documentation

Makes a cross correlation of the two input traces. This is a full (non-gated) cross correlation. To effect a gate, restrict one of the input vectors to the length of the gate.


The program is used as follows:

runXCorr input1FileName input2FileName

Where the input1FileName and input2FileName are in our standard file format.



The output of the program appears one place:

(1)   A copy of the output data is placed in the file lastDataOutput.



The formula used for this cross correlation is:




which of course is the non-gated version. (In this case,  means over all available samples.


A gated version would be over a subset of selected samples, and have the formula:




where the length of the gate would be 2N+1.


We can further generalize the formula by noting that the lengths of H and G, and the lengths of the gates of H and G need not be the same. In those cases, we can extend the values of H and G accordingly by 0 padding. This is what is done implicitly in MtConv.


Both equations produce numbers in the interval [-1,1]. 1 is achieved when ., and -1 is achieved when .


In the case of band limited data, and finite sample lengths Equation (1.2) is preferred. However, with judicious use of 0 padding, that will be the case.s



Wm P. Kamp