# `viz.transect()`

**Category:** Visualization
**Status:** experimental

## Purpose

Plot an ordered path as a horizontal distance-by-value line or a
distance-by-depth section.

## Real signature

```r
viz.transect(x, path, variable, time = NULL, depth = NULL,
             lon_col = "longitude", lat_col = "latitude", id_col = NULL,
             match = c("exact", "nearest"), tolerance = NULL,
             mode = c("auto", "section", "horizontal"),
             distance = c("requested", "matched"), limits = NULL,
             na.rm = TRUE, reverse_depth = TRUE, points = TRUE,
             title = NULL, subtitle = NULL, caption = NULL)
```

`cube_transect()` is the sole selection and matching layer. The visualization
does not densify, interpolate, reorder, average, or recalculate the path. It
returns a `ggplot` object, and lazy NetCDF extraction remains selective.

## Minimal executable check

```r
library(oceancube)
stopifnot(is.function(viz.transect))
```