gdata (version 2.18.0.1)

interleave: Interleave Rows of Data Frames or Matrices

Description

Interleave rows of data frames or Matrices.

Usage

interleave(..., append.source=TRUE, sep=": ", drop=FALSE)

Value

Matrix containing the interleaved rows of the function arguments.

Arguments

...

objects to be interleaved

append.source

Boolean Flag. When TRUE (the default) the argument name will be appended to the row names to show the source of each row.

sep

Separator between the original row name and the object name.

drop

boolean flag - When TRUE, matrices containing one column will be converted to vectors.

Author

Gregory R. Warnes

Details

This function creates a new matrix or data frame from its arguments.

The new object will have all of the rows from the source objects interleaved. IE, it will contain row 1 of object 1, followed by row 1 of object 2, .. row 1 of object 'n', row 2 of object 1, row 2 of object 2, ... row 2 of object 'n' ...

See Also

cbind, rbind, combine

Examples

# Simple example
a <- matrix(1:10,ncol=2,byrow=TRUE)
b <- matrix(letters[1:10],ncol=2,byrow=TRUE)
c <- matrix(LETTERS[1:10],ncol=2,byrow=TRUE)
interleave(a,b,c)

# Useful example:
#
# Create a 2-way table of means, standard errors, and # obs

g1 <- sample(letters[1:5], 1000, replace=TRUE)
g2 <- sample(LETTERS[1:3], 1000, replace=TRUE )
dat <- rnorm(1000)

stderr <- function(x) sqrt( var(x,na.rm=TRUE) / nobs(x) )

means   <- tapply(dat, list(g1, g2), mean )
stderrs <- tapply(dat, list(g1, g2), stderr )
ns      <- tapply(dat, list(g1, g2), nobs )
blanks <- matrix( " ", nrow=5, ncol=3)

tab <- interleave( "Mean"=round(means,2),
                   "Std Err"=round(stderrs,2),
                   "N"=ns, " " = blanks, sep=" " )

print(tab, quote=FALSE)

# Using drop to control coercion to a lower dimensions:

m1 <- matrix(1:4)
m2 <- matrix(5:8)

interleave(m1, m2, drop=TRUE)  # This will be coerced to a vector

interleave(m1, m2, drop=FALSE) # This will remain a matrix