[BioC] heatmap.2

[carol white]

Hi,
Does heatmap.2 function combine all variables into a single overall measure of dissimilarity between two observations as explained in The elements of statistical learning, Hastie et al, 2001, pp457? Does this function calculate the dissimilarity between observations and variables as follows?

         N   N    p
1/(N^2) sum sum   sum d(xij,xi'j)
        i=1 i'=1  j=1

where N is the number of observations, p the number of variables, xi and xi' are two different observations, and d is the dissimilarity between two variables, respectively. 

Any relevant information is welcome.

Best,

Carol