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DEM Small

rasterGeoTIFFEPSG:32633tinybundled

A tiny single-band float32 digital elevation model with a NaN NoData pixel. Exercises continuous-surface raster handling and the NaN NoData convention.

Pixels of dem_small, a 16x16 raster, with NoData in magenta
1 band, 16x16 px, float32, nan NoData. Rendered from the case's actual pixels, contrast-stretched for display; NoData is shown in magenta.
Property Value
Case ID dem_small
Category raster
Format GeoTIFF
CRS EPSG:32633
Location Southern Italy / Sicily (synthetic, UTM 33N) — 15.00°E, 40.65°N → 15.00°E, 40.65°N
Test tier integration
Size class tiny
Storage class bundled
Redistributable yes
Loader rasterio
Status validated

Use this case

import pytest


@pytest.mark.geocase_case("dem_small")
def test_dem_small(geocase_case) -> None:
    data = geocase_case.load()
    assert data is not None

Use GeoCase in your tests

Install the complete set of vector, raster, and NetCDF dependencies:

pip install "geocase[all]"

View GeoCase on PyPI.

What this case checks

Confirm GeoCase can open a float32 DEM, preserve its single band, and treat the NaN NoData value correctly during terrain logic.

Risk types covered

Expected behavior

Assertion Expected
expect_loadable yes
expect_crs yes
expected_epsg 32633
expect_nodata yes
expected_band_count 1
expected_dtype float32
expected_shape [16, 16]
nodata_convention nan
expected_compression deflate
expected_band_names elevation

Known answer

Computed from the actual bytes and gated against them. Grade your own output against these.

Quantity Value
Mean over valid pixels 152.2941176471
Mean including NoData 152.2941176471
NoData pixels 1
Bounds (case CRS) [500000.0, 4499840.0, 500160.0, 4500000.0]

Notes

Purpose

Elevation baseline for validating float32 continuous-surface handling and NaN NoData semantics.

What to expect

  • CRS is EPSG:32633.
  • One float32 band named elevation.
  • 16×16 pixels, DEFLATE compressed.
  • NoData is NaN (one pixel).

Typical checks

  • assert_band_count(src, 1)
  • assert_dtype(src, "float32")
  • assert_nan_nodata(src)

Common failure modes

  • NaN pixels included in min/max/mean statistics.
  • NoData convention assumed to be a numeric sentinel.

Regenerate

python scripts/generate_raster_fixtures.py

Required capabilities

  • load
  • nodata-check
  • nan-nodata-check

Files

Browse this case on GitHub

Source and license

  • Source: geocase-synthetic
  • License: MIT

Tags

delivery:single-file dem eo geography:utm geotiff product:dem raster terrain