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Mapper Algorithm

get_mapper_graph.Rd

See the following article for more details: Singh, Gurjeet, Facundo Mémoli, and Gunnar E. Carlsson. "Topological methods for the analysis of high dimensional data sets and 3d object recognition." SPBG. 2007.

Usage

get_mapper_graph(
  graph,
  filter_values,
  num_intervals = 10,
  percent_overlap = 33
)

Arguments

graph

An igraph object (n vertices).

filter_values

A numeric vector (n) of filter values, specifying how to order the vertices of the graph and thus group them into level sets.

num_intervals

An integer specifying the resolution of the Mapper algorithm (the number of level sets).

percent_overlap

A numeric between 0 and 100 specifying the gain of Mapper algorithm (the percentage that level sets should overlap).

Value

igraph object containing the Mapper graph

Examples

my_data <- makeSwissRoll()
#> Error in makeSwissRoll(): could not find function "makeSwissRoll"
my_graph <- dimRed:::makeKNNgraph(x = my_data, k = 5, eps = 0)
#> Error in h(simpleError(msg, call)): error in evaluating the argument 'x' in selecting a method for function 'nrow': object 'my_data' not found
mapper_graph <- get_mapper_graph(my_graph, my_data[, 1])
#> Error in get_mapper_graph(my_graph, my_data[, 1]): could not find function "get_mapper_graph"
get_mapper_plot(my_data, mapper_graph)
#> Error in get_mapper_plot(my_data, mapper_graph): could not find function "get_mapper_plot"