check_zero_width_intervals: Check for Zero-Width Intervals

In dataSDA: Datasets and Basic Statistics for Symbolic Data Analysis

Check for Zero-Width Intervals

Description

Checks whether interval-valued data contains any zero-width intervals (min == max). Such degenerate intervals break downstream tools that divide by interval width (e.g. ggInterval::ggInterval_indexImage()). The input may be supplied either in MM format (a data.frame with paired _min/_max columns) or in RSDA format (a symbolic_tbl with symbolic_interval columns).

Usage

check_zero_width_intervals(data, tol = 0, warn = TRUE)

Arguments

data	Interval-valued data, in one of two accepted formats: a data.frame in MM format with paired _min/_max columns, or a symbolic_tbl (RSDA format) with symbolic_interval columns. Non-interval columns (e.g. set/modal variables) are ignored.
tol	Non-negative numeric tolerance. An interval is flagged when abs(max - min) <= tol. Defaults to 0 (exact min == max).
warn	Logical; if TRUE (default) a single warning naming the affected variables is emitted when zero-width intervals are found.

Value

Invisibly, a logical scalar: TRUE if any zero-width interval is present, otherwise FALSE. The returned value carries two attributes: "flagged", a logical [n, p] matrix marking each zero-width cell (rows = concepts, columns = interval variables), and "variables", the names of variables containing at least one zero-width interval.

Examples

# MM format (paired _min/_max columns)
data(mushroom.int.mm)
check_zero_width_intervals(mushroom.int.mm)

# RSDA format (symbolic_tbl)
data(mushroom.int)
check_zero_width_intervals(mushroom.int)

dataSDA documentation built on June 12, 2026, 9:06 a.m.