colpairs {gclus}

Applies a function to all pairs of columns

Description

Given an nxp matrix m and a function f, returns the pxp matrix got by applying f to all pairs of columns of m .

Usage

colpairs(m, f, diag = 0, na.omit = FALSE, ...)

Arguments

m

a matrix

f

a function of two vectors, which returns a single result.

diag

if supplied, this value is placed on the diagonal of the result.

na.omit

If TRUE, rows with missing values are omitted for each pair of columns.

...

argments are passed to f.

Value

a matrix matrix got by applying f to all pairs of columns of m .

Author(s)

Catherine B. Hurley

See Also

gave, partition.crit, order.single,order.endlink

Examples

data(state)
state.m <- colpairs(state.x77, 
function(x,y)  cor.test(x,y,"two.sided","kendall")$estimate, diag=1)
state.col <- dmat.color(state.m)
# This is equivalent to state.m <- cor(state.x77,method="kendall")


layout(matrix(1:2,nrow=1,ncol=2))
cparcoord(state.x77, panel.color= state.col)
# Get rid of the panels with lots of line crossings (yellow) by reorderings
cparcoord(state.x77, order.endlink(state.m), state.col)
layout(matrix(1,1))


# m is a homogeneity measure of each pairwise variable plot
m <- -colpairs(scale(state.x77), gave)

o<- order.single(m)
pcols = dmat.color(m)
# Color panels by level of m and reorder variables so that
# pairs with high m are near the diagonal.
cpairs(state.x77,order=o, panel.colors=pcols)

# In this case panels showing either of Area or Population
# exhibit the most clumpiness because these variables
# are skewed.