expressionTransformation: Common higher-order functions for transforming R expressions
In rgp: R genetic programming framework

Description Usage Arguments Value

MapExpressionNodes transforms an expression expr by replacing every node in the tree with the result of applying a function f. The parameters functions, inners, and leafs control if f should be applied to the function symbols, inner subtrees, and leafs of expr, respectively. MapExpressionLeafs and MapExpressionSubtrees are shorthands for calls to MapExpressionNodes. expr. an expression expr. expr, given as list of nodes and and list of vertices. Each vertex is represented as a pair of indices into the list of nodes. AllExpressionNodes checks if all nodes in the tree of expr satisfy the predicate p (p returns TRUE for every node). This function short-cuts returning FALSE as soon as a node that does not satisfy p is encountered. AnyExpressionNode checks if any node in the tree of expr satisfies the predicate p. This function short-cuts returning TRUE as soon as a node that satisfies p is encountered. subtreeAt returns the subtree at index. replaceSubtreeAt replaces the subtree at index with replacement and returns the result.

MapExpressionNodes(f, expr, functions = TRUE, inners = FALSE,
  leafs = TRUE)

MapExpressionLeafs(f, expr)

MapExpressionSubtrees(f, expr)

FlattenExpression(expr)

subtrees(expr, functions = FALSE, inners = TRUE, leafs = TRUE)

expressionGraph(expr)

AllExpressionNodes(p, expr)

AnyExpressionNode(p, expr)

subtreeAt(expr, index)

replaceSubtreeAt(expr, index, replacement)

`f`	The function to apply.
`functions`	Whether to apply `f` to the function symbols of `expr`. Defaults to `TRUE`.
`inners`	Whether to apply `f` to the inner subtrees of `expr`. Defaults to `FALSE`.
`leafs`	Wheter to apply `f` to the leafs of `expr`. Defaults to `TRUE`.
`p`	The predicate to check.
`expr`	The expression to transform.
`index`	An in-order subtree index starting from `0` (the root).
`replacement`	An expression.