stream_sum: Stream sum of a numeric column

In shard: Deterministic, Zero-Copy Parallel Execution for R

Stream sum of a numeric column

Description

Computes the sum of col across all partitions without collecting the full dataset. When partitions are native-encoded, this avoids decoding string columns entirely.

Usage

stream_sum(x, col, na_rm = TRUE)

Arguments

x	A shard_row_groups or shard_dataset handle.
col	Column name to sum.
na_rm	Logical; drop NAs (default TRUE).

Value

A single numeric value giving the sum of the column across all partitions.

Examples

s <- schema(x = float64())
sink <- table_sink(s, mode = "row_groups")
table_write(sink, 1L, data.frame(x = c(1.0, 2.0, 3.0)))
rg <- table_finalize(sink)
stream_sum(rg, "x")

shard documentation built on April 3, 2026, 9:08 a.m.