Cumulate {data.tree}

Cumulate values among siblings

Description

For example, you can sum up values of siblings before this Node.

Usage

Cumulate(node, attribute, aggFun, ...)

Arguments

node

The node on which we want to cumulate

attribute

determines what is collected. The attribute can be

• a.) the name of a field or a property/active of each Node in the tree, e.g. acme$Get("p") or acme$Get("position")

• b.) the name of a method of each Node in the tree, e.g. acme$Get("levelZeroBased"), where e.g. acme$levelZeroBased <- function() acme$level - 1

• c.) a function, whose first argument must be a Node e.g. acme$Get(function(node) node$cost * node$p)

aggFun

the aggregation function to be applied to the children's attributes

...

any arguments to be passed on to attribute (in case it's a function)

Examples

data(acme)
acme$Do(function(x) x$cost <- Aggregate(x, "cost", sum), traversal = "post-order")
acme$Do(function(x) x$cumCost <- Cumulate(x, "cost", sum))
print(acme, "cost", "cumCost")