rep_n_stack {prettyR}

Replicate and stack columns of a data frame

Description

Reshape a data frame by stacking two or more columns into one and adding a factor, while replicating the remaining columns and stacking them to match the number of rows

Usage

 rep_n_stack(data,to.stack,stack.names=NULL)

Arguments

data

A data frame.

to.stack

Which columns are to be stacked together (see Details).

stack.names

Names for the new factor and stacked column.

Details

‘⁠rep_n_stack⁠’ takes two or more specified columns in a data frame and "stacks" them into a single column. It also creates a new factor composed of the replicated names of the columns that identifies from which column each value came. The remaining columns in the data frame are replicated to match the new number of rows.

If ‘⁠to.stack⁠’ is a matrix of names or column numbers, ‘⁠rep_n_stack⁠’ will stack each row into two new columns, allowing multiple related sets of values to be stacked in one operation.

A matrix or data frame of values can now be stacked so that the values can be displayed by a function like ‘⁠barNest⁠’ in the plotrix package.

Value

The reshaped data frame.

Note

‘⁠rep_n_stack⁠’ only does what other reshaping functions can do, but may be more easy to understand.

Author(s)

Jim Lemon

See Also

reshape

Examples

 wide.data<-data.frame(ID=1:10,Glup=sample(c("Montic","Subtic"),10,TRUE),
  Flimit1=runif(10,1,2),Flimit2=runif(10,1.5,2.5),Flimit3=runif(10,1.2,3),
  Glimit1=rnorm(10,mean=5),Glimit2=rnorm(10,mean=4),Glimit3=rnorm(10,mean=4.5))
 # first just stack one set of related measures
 rep_n_stack(wide.data[,1:5],to.stack=c("Flimit1","Flimit2","Flimit3"))
 # now stack two sets of related measures and pass names for the stacks
 rep_n_stack(wide.data,to.stack=matrix(3:8,nrow=2,byrow=TRUE),
  stack.names=c("Limit_F","Value_F","Limit_G","Value_G"))
 # finally stack a matrix of means into a single column with the
 # row and column names becoming "factor" variables
 meanmat<-matrix(runif(16,10,20),nrow=4)
 rownames(meanmat)<-c("Plunderers","Storers","Refusers","Jokers")
 colnames(meanmat)<-c("Week1","Week2","Week3","Week4")
 rep_n_stack(meanmat,to.stack=1:4,
  stack.names=c("Returns","Occasion","Strategy"))