# `link_events()`
**Category:** Selection and extraction
**Status:** stable

## Purpose
Attach nearest cube values to event rows.

## When to use
Use it when its declared input and output match the workflow. Prefer a narrower selection before any operation that may materialise values.

## When not to use
Do not use it to calculate `spatind` indicators or to bypass coordinate, CRS, unit, and provenance checks.

## Real signature
```r
link_events(x, events, lon_col = "lon", lat_col = "lat", date_col = "date",      depth_col = NULL, vars = NULL, prefix = NULL, time_tolerance = 0L,      keep_grid = TRUE)
```

## Arguments
- `x`: see the installed Rd manual for validation and defaults.
- `events`: see the installed Rd manual for validation and defaults.
- `lon_col`: see the installed Rd manual for validation and defaults.
- `lat_col`: see the installed Rd manual for validation and defaults.
- `date_col`: see the installed Rd manual for validation and defaults.
- `depth_col`: see the installed Rd manual for validation and defaults.
- `vars`: see the installed Rd manual for validation and defaults.
- `prefix`: see the installed Rd manual for validation and defaults.
- `time_tolerance`: see the installed Rd manual for validation and defaults.
- `keep_grid`: see the installed Rd manual for validation and defaults.

## Input and output
Input: **events + ocean_cube**. Output: **data.frame**.

## Backend support
Memory: **TRUE**. NetCDF: **TRUE**. Backend operations retain read-only semantics; materialisation is explicit.

## Dimensional effect
May change shape or return a non-cube analytical object; inspect dimensions/rows.

## Metadata
Units, coordinates, provenance, masks, and QA metadata are retained or reported where meaningful.

## Minimal executable check
```r
library(oceancube)
stopifnot(is.function(oceancube::link_events))
names(formals(oceancube::link_events))
```

## Example in a workflow
Typical position: `events + ocean_cube` → `link_events()` → `analysis`. See the workflow scripts for a checked end-to-end example.

## Frequent errors and limitations
Invalid dimensions, selectors, units, CRS, source-file identity, optional dependencies, or unsupported grids are rejected explicitly. Read the function Rd page for exact diagnostics.

## Related functions
Previous: `events + ocean_cube`. Next: `analysis`.