by_scale function

Scale a dataframe or matrix

Split a dataframe into a list according to the levels of variables in the dataframe and scale the numeric variables in each dataframe in the list.

scaleBy(formula, data = parent.frame(), center = TRUE, scale = TRUE)

scale_by(data, formula, center = TRUE, scale = TRUE)

Arguments

• formula: Variables to split data frame by, as as.quoted

  variables, a formula or character vector.

• data: A dataframe or matrix

• center: Logical, should data be centered.

• scale: Logical, should data be scaled.

Returns

A list of objects of same class as x

Examples

scaleBy(~Species, data=iris, center=TRUE, scale=FALSE)
scaleBy(~1, data=iris, center=TRUE, scale=FALSE)

scale_by(iris, ~Species)
scale_by(iris, ~1)

## Not combine list of dataframes to one dataframe e.g. as:
a <- scale_by(iris, ~Species)
d <- do.call(rbind, a)

See Also

orderBy, order_by, summaryBy, summary_by, transformBy, transform_by

Author(s)

Søren Højsgaard, sorenh@math.aau.dk