# `viz.map()`

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

## Purpose

Draw exactly one stored variable, time, and depth layer without interpolation.

## Real signature

```r
viz.map(x, variable, time = NULL, depth = NULL, limits = NULL,
        na.rm = TRUE, coastline = NULL, title = NULL,
        subtitle = NULL, caption = NULL)
```

The result is a `ggplot` object. Regular grids use raster cells and irregular
rectilinear grids use tiles. A lazy NetCDF input reads only the selected layer;
the scientific cube is not transformed.

## Minimal executable check

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

Use after explicit validation and selection. It also visualizes a singleton
time layer returned by `cube_trend()`.