Compute LCC sizes from downsampled edgelists

Calculates the sizes of the largest connected components (LCCs) from a set of parquet files containing downsampled edgelists.

Usage

lcc_sizes(df, mc_cores = 1)

Arguments

df

A tibble with columns:

pq_files

Paths to parquet files containing downsampled edgelists.

fracs

The corresponding downsampling fractions.

Typically generated with downsample_to_parquet.

mc_cores

Number of cores to use for parallel processing. Default is 1 (sequential processing). Values > 1 use parallel::mclapply.

Value

A tibble with columns:

component

The component (cell) identifier.

frac

The downsampling fraction.

n_nodes

The number of nodes in the largest connected component.

Details

Algorithm

For each parquet file (representing a downsampling fraction), this function:

1. Loads the edgelist into a DuckDB connection

2. Constructs a property graph using the duckpgq extension

3. Computes weakly connected components

4. Identifies the largest component for each cell

Performance

The duckpgq extension enables efficient graph operations without loading the full edgelist into memory. Parallel processing across fractions is supported via mc_cores.

See also

downsample_to_parquet for generating the input parquet files. lcc_curve for a high-level wrapper.