# `viz.section()`

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

## Purpose

Draw a stored longitude-depth or latitude-depth plane at one historical time.

## Real signature

```r
viz.section(x, variable,
            section = c("longitude-depth", "latitude-depth"),
            time = NULL, longitude = NULL, latitude = NULL, depth = NULL,
            limits = NULL, na.rm = TRUE, reverse_depth = TRUE,
            title = NULL, subtitle = NULL, caption = NULL)
```

The result is a `ggplot` object. The function fixes the complementary
horizontal coordinate, requires at least two depth levels, and neither
aggregates nor interpolates. A lazy NetCDF source reads only the selected
plane.

## Minimal executable check

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