hamlet (version 0.9.6)

mix.binary: Binary coding of categorical variables

Description

This function encodes categorical variables (e.g. columns of type 'factor' or 'character'). U new columns are created per each such column, where U is the number of unique instances of that column. The new columns are named OriginalColumnName_U1, OriginalColumnName_U2, etc.

Usage

mix.binary(x)

Arguments

x

A data.frame or a matrix where categorical columns are to be binary coded. Categorical columns are assumed to be all non-numeric fields.

Value

The function returns a data.frame, where categorical variables have been replaced with 0/1-binary fields, and numeric fields have been left untouched. Notice that the order of the columns may not be the original.

Details

A function that codes categorical variables in a dataset into binary variables. This is done in the following manner: e.g. x = red, green, blue, green --> x_new = 1,0,0, 0,1,0, 0,0,1, 0,1,0 where the dimensions in x_new are is_red, is_green and is_blue

Examples

# NOT RUN {
data(vcapwide)

ex <- mix.binary(vcapwide[,c("Group", "CastrationDate")])
apply(ex, MARGIN=1, FUN=sum) 
# Notice that each row sums to 2, as two categorical variables were binary coded 
# and no missing values were present

mix.binary(vcapwide[,c("PSAWeek4", "Group", "CastrationDate")]) 
# Binary coding is only applied to non-numeric fields
# }