feat(eda): primitivas geoespaciales del grupo eda (detección lat/lon + extensión + scatter)

Tres funciones puras nuevas del dominio datascience (tags eda + geospatial) que
sostienen el capítulo GEOSPATIAL del AutomaticEDA, delegadas a fn-constructor:

- detect_latlon_columns: identifica el par (lat, lon) por nombre de columna +
  rango de valores ([-90,90] / [-180,180]) desde profile['columns']. Devuelve
  {lat_col, lon_col, confidence, reason}. 9 tests.
- analyze_geo_extent: bbox, centroide, span haversine, conteo por zona/país
  (lookup offline con bounding boxes embebidos, KISS sin geopandas) y
  hemisferios. 7 tests.
- build_geo_scatter: prepara los puntos del scatter en orden [lon, lat] con
  downsampling determinista por paso fijo + aspect equirectangular 1/cos(lat)
  clampado. 6 tests.

Registradas en datascience/__init__.py. Todas pure, params_schema completo,
.md autosuficiente (Ejemplo + Cuando usarla + Gotchas).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

python/functions/datascience/__init__.py

@@ -44,6 +44,9 @@ from .trend_slope import trend_slope
 from .run_eda_models import run_eda_models
 from .project_clusters_2d import project_clusters_2d
 from .describe_clusters_llm import describe_clusters_llm
+from .detect_latlon_columns import detect_latlon_columns
+from .analyze_geo_extent import analyze_geo_extent
+from .build_geo_scatter import build_geo_scatter
 from .eda_llm_insights import eda_llm_insights
 from .build_eda_notebook import build_eda_notebook
 from .decode_qr_image import decode_qr_image
@@ -90,6 +93,9 @@ __all__ = [
     "run_eda_models",
     "project_clusters_2d",
     "describe_clusters_llm",
+    "detect_latlon_columns",
+    "analyze_geo_extent",
+    "build_geo_scatter",
     "eda_llm_insights",
     "build_eda_notebook",
     "describe_numeric",

python/functions/datascience/analyze_geo_extent.md

@@ -0,0 +1,61 @@
+---
+name: analyze_geo_extent
+kind: function
+lang: py
+domain: datascience
+version: "1.0.0"
+purity: pure
+signature: "def analyze_geo_extent(lats: list, lons: list) -> dict"
+description: "Calcula la extension geografica de una nube de coordenadas (lat/lon) y asigna cada punto a un pais/region mediante un lookup OFFLINE contra una tabla de bounding boxes embebida como constante. Devuelve bounding box, centroide, span de la diagonal (haversine), conteo por region (top-8 + Otros), reparto por hemisferios y una frase resumen en ES. Lectura defensiva: descarta pares None/NaN/fuera de rango y NUNCA lanza. Solo stdlib (math); sin geopandas/shapely. Las cajas de paises son rectangulos aproximados, no reverse-geocoding exacto."
+tags: [eda, geospatial, geo, coordinates, bounding-box, haversine, datascience]
+params:
+  - name: lats
+    desc: "Lista de latitudes en grados, rango valido [-90, 90]. Se empareja por indice con lons (gana la longitud minima comun si difieren). Cada valor puede ser None/NaN/no-numerico/fuera de rango: se lee defensivo y se descarta el par."
+  - name: lons
+    desc: "Lista de longitudes en grados, rango valido [-180, 180]. Paralela a lats, emparejada por indice. Valores None/NaN/no-numericos/fuera de rango se descartan junto con su par."
+output: "Dict con el resumen geografico: {n_points=pares validos usados, bbox={lat_min,lat_max,lon_min,lon_max} o None, centroid={lat,lon}=media de lat/lon validos o None, span_km=distancia haversine (radio 6371 km) de la diagonal SO->NE del bbox, by_region=[{region,count}] descendente por count limitado a top-8 con el resto agregado en 'Otros', hemisphere={north,south,east,west} (ecuador->norte, meridiano 0->este), note=frase ES resumen}. Si no hay pares validos devuelve la forma cero: n_points 0, bbox None, centroid None, span_km 0.0, by_region [], hemisphere a ceros y note 'sin coordenadas validas'. Puntos que no caen en ninguna caja -> region 'Oceano/Otros'."
+uses_functions: []
+uses_types: []
+returns: []
+returns_optional: false
+error_type: ""
+imports: [math]
+tested: true
+tests: ["test_nube_en_espana", "test_dos_paises_distintos", "test_listas_vacias", "test_pares_invalidos_filtrados", "test_longitudes_desbalanceadas", "test_span_km_haversine_par_conocido", "test_no_lanza_con_entradas_raras"]
+test_file_path: "python/functions/datascience/analyze_geo_extent_test.py"
+file_path: "python/functions/datascience/analyze_geo_extent.py"
+---
+
+## Ejemplo
+
+```python
+import sys, os
+sys.path.insert(0, os.path.join("python", "functions"))
+from datascience.analyze_geo_extent import analyze_geo_extent
+
+# Nube de puntos alrededor de Madrid + un punto en Paris.
+lats = [40.4, 40.0, 41.0, 48.8]
+lons = [-3.7, -3.5, -4.0, 2.3]
+res = analyze_geo_extent(lats, lons)
+
+print(res["n_points"])          # 4
+print(res["by_region"])         # [{'region': 'España', 'count': 3}, {'region': 'Francia', 'count': 1}]
+print(round(res["span_km"], 1)) # diagonal SO->NE del bbox en km
+print(res["hemisphere"])        # {'north': 4, 'south': 0, 'east': 1, 'west': 3}
+print(res["note"])              # los puntos se concentran en España (3 de 4)
+```
+
+## Cuando usarla
+
+- Usala en el perfilado EDA (grupo `eda`) cuando una tabla tenga columnas de latitud y longitud y quieras un resumen geografico rapido: donde se concentran los puntos, cuanto territorio cubren y a que paises/regiones caen, sin montar geopandas ni un reverse-geocoder.
+- Cuando necesites un capitulo `geospatial` del `AutomaticEDA`: alimenta el bbox + centroide para centrar un mapa, el `span_km` para elegir el zoom, y `by_region` para una tabla de conteos por pais.
+- Cuando quieras detectar datos sucios de coordenadas (mezcla de hemisferios inesperada, puntos en `Oceano/Otros`, span enorme) antes de seguir el analisis.
+
+## Gotchas
+
+- Funcion pura, sin I/O ni red y determinista: mismas entradas -> misma salida. Lectura defensiva, NUNCA lanza; pares con None/NaN o fuera de rango ([-90,90] lat, [-180,180] lon) se descartan en silencio.
+- El lookup de region es una **aproximacion rectangular**: cada pais/region es un bounding box, NO su frontera real. Un punto en el mar cerca de una costa, o en una esquina del rectangulo, puede asignarse a un pais vecino. No es reverse-geocoding exacto — para precision real hace falta un shapefile (fuera de scope por KISS).
+- Cajas solapadas se resuelven por orden: gana la PRIMERA que contiene el punto. Los paises se listan antes que los continentes (fallback), y entre vecinos el mas estrecho/occidental va primero (Portugal antes que España, Chile antes que Argentina, EEUU contiguo antes que Canada). Un punto que no cae en ninguna caja -> `Oceano/Otros`.
+- La tabla cubre ~24 paises grandes + 6 regiones continentales; paises pequeños o no listados caen a su continente o a `Oceano/Otros`. No incluye territorios insulares lejanos (Canarias, Hawaii, etc.).
+- `span_km` es la diagonal del bounding box (esquina SO a NE), no la dispersion real de la nube ni el area; con un solo punto valido el bbox es degenerado y `span_km` es 0.0.
+- El ecuador (`lat == 0`) cuenta como hemisferio norte y el meridiano 0 (`lon == 0`) como este, por convencion `>= 0`.

python/functions/datascience/analyze_geo_extent.py

@@ -0,0 +1,209 @@
+"""analyze_geo_extent — geographic extent of a cloud of coordinates (EDA `geospatial`).
+
+Pure function: no I/O, no network, deterministic. Given two parallel lists of
+latitudes and longitudes it derives the bounding box, centroid, diagonal span
+(haversine), per-region counts and hemisphere split of the points, and assigns
+each point to a country/region via an OFFLINE lookup against a table of
+rectangular bounding boxes embedded as a constant (`_REGION_BBOXES`).
+
+It never reads files, never hits the network and depends only on `math`. The
+country boxes are deliberately coarse rectangles (a KISS approximation, NOT a
+reverse-geocoder). Reading is defensive throughout and the function NEVER
+raises: invalid pairs (None / NaN / out of range) are silently discarded and an
+empty cloud yields a zeroed result the caller can skip.
+"""
+
+import math
+
+# Earth mean radius in km used by the haversine formula.
+_EARTH_RADIUS_KM = 6371.0
+
+# How many distinct regions to surface in `by_region` before collapsing the
+# remainder into a single "Otros" bucket.
+_TOP_REGIONS = 8
+
+# Offline region lookup: (name, lat_min, lat_max, lon_min, lon_max).
+#
+# Specific countries are listed FIRST and continental fallbacks LAST: each point
+# is assigned to the FIRST box that contains it, so the more specific country box
+# wins over the broad continent box. Boxes are coarse rectangles approximating
+# the mainland extent of each region; overlapping neighbours are ordered so the
+# narrower/more-western country claims its coastal points (e.g. Portugal before
+# Spain, Chile before Argentina, the contiguous US before Canada).
+_REGION_BBOXES = (
+    # --- countries (specific) ---
+    ("Portugal", 36.9, 42.2, -9.6, -6.2),
+    ("España", 36.0, 43.8, -9.4, 3.4),
+    ("Francia", 41.3, 51.1, -5.2, 9.6),
+    ("Reino Unido", 49.9, 58.7, -8.6, 1.8),
+    ("Irlanda", 51.4, 55.4, -10.6, -5.9),
+    ("Países Bajos", 50.7, 53.6, 3.3, 7.2),
+    ("Bélgica", 49.5, 51.5, 2.5, 6.4),
+    ("Suiza", 45.8, 47.8, 5.9, 10.5),
+    ("Alemania", 47.3, 55.1, 5.9, 15.0),
+    ("Italia", 36.6, 47.1, 6.6, 18.5),
+    ("Marruecos", 27.7, 35.9, -13.2, -1.0),
+    ("Egipto", 22.0, 31.7, 25.0, 35.0),
+    ("Sudáfrica", -34.8, -22.1, 16.5, 32.9),
+    ("China", 18.0, 53.6, 73.5, 135.1),
+    ("Japón", 24.0, 45.6, 122.9, 145.9),
+    ("India", 6.7, 35.5, 68.1, 97.4),
+    ("Australia", -43.7, -10.0, 112.9, 153.7),
+    ("México", 14.5, 32.7, -118.4, -86.7),
+    ("Estados Unidos", 24.4, 49.4, -125.0, -66.9),
+    ("Canadá", 41.7, 83.1, -141.0, -52.6),
+    ("Chile", -55.9, -17.5, -75.6, -66.4),
+    ("Argentina", -55.1, -21.8, -73.6, -53.6),
+    ("Brasil", -33.8, 5.3, -74.0, -34.8),
+    ("Rusia", 41.2, 77.0, 19.6, 180.0),
+    # --- continental fallbacks (broad) ---
+    ("Europa", 34.0, 72.0, -25.0, 45.0),
+    ("África", -35.0, 37.5, -18.0, 52.0),
+    ("Asia", 5.0, 78.0, 26.0, 180.0),
+    ("América del Norte", 7.0, 84.0, -168.0, -52.0),
+    ("América del Sur", -56.0, 13.0, -82.0, -34.0),
+    ("Oceanía", -50.0, 0.0, 110.0, 180.0),
+)
+
+
+def _coord(value, limit):
+    """Coerce a coordinate to a valid float in [-limit, limit] or None.
+
+    bool is a subclass of int but never a real coordinate, so True/False are
+    treated as missing. NaN and out-of-range values are rejected.
+    """
+    if value is None or isinstance(value, bool):
+        return None
+    try:
+        f = float(value)
+    except (TypeError, ValueError):
+        return None
+    # NaN is the only value that is not equal to itself.
+    if f != f or f < -limit or f > limit:
+        return None
+    return f
+
+
+def _haversine_km(lat1, lon1, lat2, lon2):
+    """Great-circle distance in km between two (lat, lon) points in degrees."""
+    rlat1, rlat2 = math.radians(lat1), math.radians(lat2)
+    dlat = math.radians(lat2 - lat1)
+    dlon = math.radians(lon2 - lon1)
+    a = math.sin(dlat / 2.0) ** 2 + math.cos(rlat1) * math.cos(rlat2) * math.sin(dlon / 2.0) ** 2
+    return 2.0 * _EARTH_RADIUS_KM * math.asin(min(1.0, math.sqrt(a)))
+
+
+def _region_of(lat, lon):
+    """Return the name of the first embedded box containing (lat, lon)."""
+    for name, lat_min, lat_max, lon_min, lon_max in _REGION_BBOXES:
+        if lat_min <= lat <= lat_max and lon_min <= lon <= lon_max:
+            return name
+    return "Océano/Otros"
+
+
+def _empty_result():
+    """Result shape when there are no valid coordinate pairs."""
+    return {
+        "n_points": 0,
+        "bbox": None,
+        "centroid": None,
+        "span_km": 0.0,
+        "by_region": [],
+        "hemisphere": {"north": 0, "south": 0, "east": 0, "west": 0},
+        "note": "sin coordenadas validas",
+    }
+
+
+def analyze_geo_extent(lats: list, lons: list) -> dict:
+    """Summarise the geographic extent of a cloud of lat/lon coordinates.
+
+    Pairs `lats[i]` with `lons[i]` by index (over the common length when the two
+    lists differ in size), discards any pair where either value is None / NaN or
+    outside [-90, 90] (lat) / [-180, 180] (lon), and derives the bounding box,
+    centroid, diagonal span, per-region counts and hemisphere split. Each valid
+    point is matched to a country/region by an offline lookup against coarse
+    rectangular bounding boxes (`_REGION_BBOXES`).
+
+    Args:
+        lats: List of latitudes in degrees ([-90, 90]); read defensively.
+        lons: List of longitudes in degrees ([-180, 180]); read defensively.
+            Paired with `lats` by index; the shorter length wins when they differ.
+
+    Returns:
+        Dict with the geographic summary:
+        {n_points, bbox={lat_min,lat_max,lon_min,lon_max}, centroid={lat,lon},
+         span_km (haversine of the SW->NE bbox diagonal), by_region=[{region,count}]
+         (descending, top-8 with the rest folded into "Otros"),
+         hemisphere={north,south,east,west}, note (Spanish summary phrase)}.
+        With no valid pairs returns the zeroed shape: n_points 0, bbox None,
+        centroid None, span_km 0.0, empty by_region, zeroed hemisphere and the
+        note "sin coordenadas validas". Never raises.
+    """
+    if not isinstance(lats, (list, tuple)) or not isinstance(lons, (list, tuple)):
+        return _empty_result()
+
+    valid = []
+    # zip already stops at the shorter list -> unbalanced lengths are handled.
+    for raw_lat, raw_lon in zip(lats, lons):
+        lat = _coord(raw_lat, 90.0)
+        lon = _coord(raw_lon, 180.0)
+        if lat is None or lon is None:
+            continue
+        valid.append((lat, lon))
+
+    if not valid:
+        return _empty_result()
+
+    n = len(valid)
+    lat_vals = [p[0] for p in valid]
+    lon_vals = [p[1] for p in valid]
+
+    lat_min, lat_max = min(lat_vals), max(lat_vals)
+    lon_min, lon_max = min(lon_vals), max(lon_vals)
+
+    centroid_lat = sum(lat_vals) / n
+    centroid_lon = sum(lon_vals) / n
+
+    # Diagonal span: SW corner (lat_min, lon_min) to NE corner (lat_max, lon_max).
+    span_km = _haversine_km(lat_min, lon_min, lat_max, lon_max)
+
+    # Hemisphere split: the equator/prime-meridian go to north/east respectively.
+    north = sum(1 for lat in lat_vals if lat >= 0.0)
+    south = n - north
+    east = sum(1 for lon in lon_vals if lon >= 0.0)
+    west = n - east
+
+    # Count points per region (offline bbox lookup).
+    counts = {}
+    for lat, lon in valid:
+        region = _region_of(lat, lon)
+        counts[region] = counts.get(region, 0) + 1
+
+    # Descending by count, then by name for a deterministic tie-break.
+    ranked = sorted(counts.items(), key=lambda kv: (-kv[1], kv[0]))
+    by_region = [{"region": name, "count": count} for name, count in ranked[:_TOP_REGIONS]]
+    rest = sum(count for _, count in ranked[_TOP_REGIONS:])
+    if rest > 0:
+        by_region.append({"region": "Otros", "count": rest})
+
+    top_region, top_count = ranked[0]
+    note = (
+        "los puntos se concentran en {region} ({count} de {n})".format(
+            region=top_region, count=top_count, n=n
+        )
+    )
+
+    return {
+        "n_points": n,
+        "bbox": {
+            "lat_min": lat_min,
+            "lat_max": lat_max,
+            "lon_min": lon_min,
+            "lon_max": lon_max,
+        },
+        "centroid": {"lat": centroid_lat, "lon": centroid_lon},
+        "span_km": span_km,
+        "by_region": by_region,
+        "hemisphere": {"north": north, "south": south, "east": east, "west": west},
+        "note": note,
+    }

python/functions/datascience/analyze_geo_extent_test.py

@@ -0,0 +1,126 @@
+"""Tests para analyze_geo_extent."""
+
+import math
+import os
+import sys
+
+sys.path.insert(0, os.path.dirname(__file__))
+
+from analyze_geo_extent import analyze_geo_extent, _haversine_km
+
+# Keys that a non-empty result dict must always contain.
+_EXPECTED_KEYS = {
+    "n_points", "bbox", "centroid", "span_km",
+    "by_region", "hemisphere", "note",
+}
+
+
+def test_nube_en_espana():
+    """Golden: nube de puntos alrededor de Madrid -> region top = España."""
+    # Cuatro puntos en torno a Madrid (lat ~40, lon ~-3.7), con algo de spread.
+    lats = [40.4, 40.0, 41.0, 39.5]
+    lons = [-3.7, -3.5, -4.0, -3.2]
+    res = analyze_geo_extent(lats, lons)
+
+    assert set(res.keys()) == _EXPECTED_KEYS
+    assert res["n_points"] == 4
+
+    # Todos caen en España -> by_region una sola entrada.
+    assert res["by_region"][0]["region"] == "España"
+    assert res["by_region"][0]["count"] == 4
+
+    # Centroide coherente: media de lat y lon.
+    assert math.isclose(res["centroid"]["lat"], sum(lats) / 4, rel_tol=1e-9)
+    assert math.isclose(res["centroid"]["lon"], sum(lons) / 4, rel_tol=1e-9)
+
+    # bbox correcto.
+    assert res["bbox"]["lat_min"] == 39.5
+    assert res["bbox"]["lat_max"] == 41.0
+    assert res["bbox"]["lon_min"] == -4.0
+    assert res["bbox"]["lon_max"] == -3.2
+
+    # Hay spread -> diagonal > 0.
+    assert res["span_km"] > 0.0
+
+    # Hemisferio norte (lat>0) y oeste (lon<0).
+    assert res["hemisphere"]["north"] == 4
+    assert res["hemisphere"]["south"] == 0
+    assert res["hemisphere"]["east"] == 0
+    assert res["hemisphere"]["west"] == 4
+
+    assert "España" in res["note"]
+
+
+def test_dos_paises_distintos():
+    """Golden: puntos en España y Francia -> by_region con 2 entradas."""
+    # Madrid (España) x2 y Paris (Francia) x1.
+    lats = [40.4, 40.0, 48.8]
+    lons = [-3.7, -3.5, 2.3]
+    res = analyze_geo_extent(lats, lons)
+
+    assert res["n_points"] == 3
+    regions = {entry["region"]: entry["count"] for entry in res["by_region"]}
+    assert regions == {"España": 2, "Francia": 1}
+    # Orden descendente por count: España (2) antes que Francia (1).
+    assert res["by_region"][0]["region"] == "España"
+    assert res["by_region"][0]["count"] == 2
+
+    # Madrid y Paris ambos hemisferio norte; Paris lon>0 -> 1 east, 2 west.
+    assert res["hemisphere"]["north"] == 3
+    assert res["hemisphere"]["east"] == 1
+    assert res["hemisphere"]["west"] == 2
+
+
+def test_listas_vacias():
+    """Edge: listas vacias -> n_points 0, bbox None, sin lanzar."""
+    res = analyze_geo_extent([], [])
+    assert res["n_points"] == 0
+    assert res["bbox"] is None
+    assert res["centroid"] is None
+    assert res["span_km"] == 0.0
+    assert res["by_region"] == []
+    assert res["hemisphere"] == {"north": 0, "south": 0, "east": 0, "west": 0}
+    assert res["note"] == "sin coordenadas validas"
+
+
+def test_pares_invalidos_filtrados():
+    """Edge: None / NaN / fuera de rango se descartan, no lanza."""
+    nan = float("nan")
+    lats = [40.4, None, nan, 91.0, -200.0, 40.0]
+    lons = [-3.7, -3.5, -3.0, 2.0, 5.0, -3.5]
+    # Validos: indices 0 y 5 (lat 91 fuera de rango, lon -200 fuera de rango,
+    # None y NaN descartados).
+    res = analyze_geo_extent(lats, lons)
+    assert res["n_points"] == 2
+    assert res["by_region"][0]["region"] == "España"
+    assert res["by_region"][0]["count"] == 2
+
+
+def test_longitudes_desbalanceadas():
+    """Edge: len(lats) != len(lons) usa el minimo comun sin lanzar."""
+    lats = [40.4, 40.0, 41.0, 39.5]  # 4 elementos
+    lons = [-3.7, -3.5]              # 2 elementos
+    res = analyze_geo_extent(lats, lons)
+    # Solo se emparejan los 2 primeros.
+    assert res["n_points"] == 2
+    assert res["bbox"]["lat_min"] == 40.0
+    assert res["bbox"]["lat_max"] == 40.4
+
+
+def test_span_km_haversine_par_conocido():
+    """Edge: span_km coincide con haversine de la diagonal del bbox."""
+    # Dos puntos: (0, 0) y (0, 1). bbox diagonal = mismos dos puntos.
+    res = analyze_geo_extent([0.0, 0.0], [0.0, 1.0])
+    # 1 grado de longitud en el ecuador ~ 111.19 km.
+    expected = _haversine_km(0.0, 0.0, 0.0, 1.0)
+    assert math.isclose(res["span_km"], expected, rel_tol=1e-9)
+    assert math.isclose(res["span_km"], 111.19, abs_tol=0.5)
+
+
+def test_no_lanza_con_entradas_raras():
+    """Edge: tipos no-lista o None devuelven la forma vacia sin lanzar."""
+    assert analyze_geo_extent(None, None)["n_points"] == 0
+    assert analyze_geo_extent("foo", "bar")["n_points"] == 0
+    # Strings dentro de las listas se descartan como invalidos.
+    res = analyze_geo_extent(["x", 40.0], [None, -3.5])
+    assert res["n_points"] == 1

python/functions/datascience/build_geo_scatter.md

@@ -0,0 +1,68 @@
+---
+name: build_geo_scatter
+kind: function
+lang: py
+domain: datascience
+version: "1.0.0"
+purity: pure
+signature: "def build_geo_scatter(lats: list, lons: list, max_points: int = 2000) -> dict"
+description: "Prepara los datos de un scatter geografico en proyeccion equirectangular para el grupo eda. Empareja lats/lons por indice, descarta pares None/NaN/inf/bool o fuera de rango (lat en [-90,90], lon en [-180,180]) y aplica downsampling DETERMINISTA por paso fijo (pairs[::step]) cuando hay mas pares validos que max_points, para no saturar el PDF/PPTX en moviles. Devuelve los puntos en orden [lon, lat] listos para ax.scatter, el bbox, el aspect 1/cos(centroid_lat) clampado a [0.3,5.0] y un pad sugerido (~5% del rango con suelo minimo). Lectura defensiva; NUNCA lanza ni dibuja: el capitulo se encarga de matplotlib."
+tags: [eda, geospatial, datascience, scatter, map, downsample, equirectangular, profiling]
+params:
+  - name: lats
+    desc: "Lista (o tupla) de latitudes en grados, paralela a lons. Se empareja por indice. Un valor None, NaN, infinito, bool o fuera de [-90,90] descarta ese par. Lectura defensiva."
+  - name: lons
+    desc: "Lista (o tupla) de longitudes en grados, paralela a lats. Un valor None, NaN, infinito, bool o fuera de [-180,180] descarta ese par."
+  - name: max_points
+    desc: "Tope de puntos a devolver (default 2000). Si los pares validos superan el tope, se hace downsampling determinista por paso fijo step=ceil(n_total/max_points) tomando pairs[::step] (NO aleatorio, reproducible). Un valor no entero o <=0 desactiva el downsampling."
+output: "Dict listo para dibujar: {points: [[lon, lat], ...] en orden x=lon/y=lat para ax.scatter; n_total: pares validos antes del downsample (int); n_shown: puntos devueltos tras el downsample (int); downsampled: bool (n_shown<n_total); bbox: {lat_min, lat_max, lon_min, lon_max} o None si no hay puntos; aspect: 1/cos(centroid_lat) clampado a [0.3,5.0] para no estirar la proyeccion equirectangular; pad: {lon, lat} ~5% del rango respectivo con suelo minimo 0.01 grados}. Si no hay pares validos: points=[], n_total=0, n_shown=0, downsampled=False, bbox=None, aspect=1.0, pad={lon:0.0, lat:0.0}."
+uses_functions: []
+uses_types: []
+returns: []
+returns_optional: false
+error_type: ""
+imports: []
+tested: true
+tests: ["test_geo_scatter_nube_espana", "test_downsampling_determinista_y_reproducible", "test_listas_vacias_no_lanza", "test_un_solo_punto_pad_minimo_y_aspect_finito", "test_filtra_none_nan_y_fuera_de_rango", "test_latitud_alta_aspect_clamped"]
+test_file_path: "python/functions/datascience/build_geo_scatter_test.py"
+file_path: "python/functions/datascience/build_geo_scatter.py"
+---
+
+## Ejemplo
+
+```python
+import sys, os
+sys.path.insert(0, os.path.join("python", "functions"))
+from datascience.build_geo_scatter import build_geo_scatter
+
+# Nube de coordenadas (lat, lon) alrededor de Madrid:
+lats = [40.0, 41.0, 39.0, 40.5]
+lons = [-3.7, -3.0, -4.0, -3.5]
+geo = build_geo_scatter(lats, lons, max_points=2000)
+
+print(geo["points"][0])     # [-3.7, 40.0]  -> orden [x=lon, y=lat]
+print(geo["bbox"])          # {'lat_min': 39.0, 'lat_max': 41.0, 'lon_min': -4.0, 'lon_max': -3.0}
+print(round(geo["aspect"], 3))  # 1.308  -> ensancha el eje x en latitudes medias
+print(geo["pad"])           # {'lon': 0.05, 'lat': 0.1}  -> margen ~5%
+
+# El capitulo dibuja con matplotlib (esta funcion NO dibuja):
+#   xs = [p[0] for p in geo["points"]]; ys = [p[1] for p in geo["points"]]
+#   ax.scatter(xs, ys); ax.set_aspect(geo["aspect"])
+#   ax.set_xlim(geo["bbox"]["lon_min"] - geo["pad"]["lon"], geo["bbox"]["lon_max"] + geo["pad"]["lon"])
+#   ax.set_ylim(geo["bbox"]["lat_min"] - geo["pad"]["lat"], geo["bbox"]["lat_max"] + geo["pad"]["lat"])
+```
+
+## Cuando usarla
+
+- Usala antes de dibujar un scatter geografico (mapa de puntos en proyeccion equirectangular) en el capitulo geospatial de `AutomaticEDA`: limpia los pares de coordenadas, los reduce a un tamano razonable para el PDF/PPTX y te da bbox, aspect y pad listos para fijar los ejes.
+- Cuando tengas dos columnas de lat/lon ya extraidas y quieras un punto de entrada determinista (mismo dataset -> mismo dibujo) que no sature el documento en moviles.
+- Cuando necesites el aspect correcto para que un grado de longitud no se vea estirado respecto a uno de latitud (integridad visual, Tufte) sin calcularlo a mano.
+
+## Gotchas
+
+- Funcion pura, sin I/O y determinista. NO dibuja: solo PREPARA los datos; el capitulo se encarga de matplotlib. Lectura defensiva: pares con None/NaN/inf/bool o coordenadas fuera de rango se descartan en silencio y NUNCA lanza.
+- El downsampling es DETERMINISTA por paso fijo (`step = ceil(n_total / max_points)`, `pairs[::step]`), NO aleatorio: la misma entrada produce siempre la misma salida (reproducible en tests). El primer punto mostrado es siempre el primer par valido. No es un muestreo uniforme aleatorio — es un barrido regular del orden de entrada.
+- `points` va en orden `[lon, lat]` (x, y), no `[lat, lon]`: pasalo directo a `ax.scatter(xs, ys)` sin invertir. Confundir el orden espeja el mapa.
+- `aspect = 1/cos(centroid_lat)` se clampa a `[0.3, 5.0]`. En latitudes altas `cos -> 0` y el valor real explota: por encima de ~78 grados el aspect queda fijado en 5.0. Si el centroide cae justo en un polo (`+-90`) se usa el clamp en vez de dividir por cero.
+- `pad` es ~5% del rango de cada eje con un suelo minimo de `0.01` grados: con un solo punto o todos iguales (rango 0) el pad cae al suelo para que el punto no quede en una linea. En el caso sin puntos validos el pad es `{lon:0.0, lat:0.0}` y `bbox` es `None`.
+- `bbox`, `aspect` y `pad` se calculan sobre los puntos YA mostrados (tras el downsample), de modo que los ejes encajan exactamente con lo que se dibuja.

python/functions/datascience/build_geo_scatter.py

@@ -0,0 +1,153 @@
+"""build_geo_scatter — prepare points for a geographic scatter (EDA `geospatial`).
+
+Pure function: no I/O, deterministic. Takes two parallel lists of latitudes and
+longitudes and returns the data a caller needs to draw a geographic scatter in an
+equirectangular projection: cleaned points in [lon, lat] order, a bounding box, a
+projection aspect ratio and a suggested axis padding.
+
+It NEVER draws anything (no matplotlib) — the chapter that consumes this output is
+responsible for the rendering. Reading is defensive throughout and the function
+NEVER raises: malformed pairs (None, NaN, infinity or out-of-range coordinates)
+are silently dropped and an empty/valid result is always returned.
+
+To keep the rendered PDF/PPTX light on phones, when the number of valid pairs
+exceeds `max_points` the points are down-sampled DETERMINISTICALLY by a fixed
+step (`pairs[::step]`), never randomly, so the result is reproducible.
+"""
+
+import math
+
+# Minimum axis padding (in degrees) so a single point or a zero-range cloud is
+# never drawn glued to the axis border (it would collapse to a line).
+_MIN_PAD = 0.01
+
+# Aspect ratio clamp. 1/cos(lat) blows up near the poles; clamp keeps the render
+# sane (Tufte: do not let the projection stretch the cloud out of proportion).
+_ASPECT_MIN = 0.3
+_ASPECT_MAX = 5.0
+
+
+def _coord(value):
+    """Coerce to a finite float defensively; return None for invalid coordinates.
+
+    bool is a subclass of int, but a real latitude/longitude is never a bool, so
+    True/False are treated as missing instead of coercing to 1.0/0.0. NaN and
+    +/-infinity are never valid coordinates either.
+    """
+    if value is None or isinstance(value, bool):
+        return None
+    try:
+        coord = float(value)
+    except (TypeError, ValueError):
+        return None
+    if math.isnan(coord) or math.isinf(coord):
+        return None
+    return coord
+
+
+def build_geo_scatter(lats: list, lons: list, max_points: int = 2000) -> dict:
+    """Prepare the data for a geographic scatter in equirectangular projection.
+
+    Pairs `lats` and `lons` by index, drops invalid pairs, optionally
+    down-samples deterministically, and derives the geometry (bbox, aspect, pad)
+    a caller needs to draw the cloud. No raw rendering is performed.
+
+    Args:
+        lats: List (or tuple) of latitudes in degrees. Paired by index with
+            `lons`. A value that is None, NaN, infinite, bool or outside
+            [-90, 90] discards that pair. Read defensively.
+        lons: List (or tuple) of longitudes in degrees, parallel to `lats`. A
+            value outside [-180, 180] (or None/NaN/inf/bool) discards that pair.
+        max_points: Cap on the number of points returned. When the number of
+            valid pairs exceeds this cap, the points are down-sampled by a fixed
+            step `ceil(n_total / max_points)` taking `pairs[::step]` — DETERMINISTIC,
+            not random, so the output is reproducible. A non-positive or non-int
+            value disables down-sampling.
+
+    Returns:
+        Dict ready for a caller's ax.scatter:
+        {points: [[lon, lat], ...] (x=lon, y=lat order), n_total: valid pairs
+        before down-sampling, n_shown: points returned, downsampled: bool,
+        bbox: {lat_min, lat_max, lon_min, lon_max} or None, aspect: 1/cos(centroid
+        lat) clamped to [0.3, 5.0], pad: {lon, lat} ~5% of each range with a small
+        floor}. When there are no valid pairs returns points=[], n_total=0,
+        n_shown=0, downsampled=False, bbox=None, aspect=1.0, pad={lon:0.0, lat:0.0}.
+    """
+    pairs = []  # each item is (lon, lat) — already in [x, y] order
+    if isinstance(lats, (list, tuple)) and isinstance(lons, (list, tuple)):
+        n = min(len(lats), len(lons))
+        for i in range(n):
+            lat = _coord(lats[i])
+            lon = _coord(lons[i])
+            if lat is None or lon is None:
+                continue
+            if lat < -90.0 or lat > 90.0:
+                continue
+            if lon < -180.0 or lon > 180.0:
+                continue
+            pairs.append((lon, lat))
+
+    n_total = len(pairs)
+    if n_total == 0:
+        return {
+            "points": [],
+            "n_total": 0,
+            "n_shown": 0,
+            "downsampled": False,
+            "bbox": None,
+            "aspect": 1.0,
+            "pad": {"lon": 0.0, "lat": 0.0},
+        }
+
+    # Deterministic down-sampling by a fixed step. Reproducible: same input ->
+    # same output, no randomness.
+    if (
+        isinstance(max_points, int)
+        and not isinstance(max_points, bool)
+        and max_points > 0
+        and n_total > max_points
+    ):
+        step = math.ceil(n_total / max_points)
+        sampled = pairs[::step]
+    else:
+        sampled = pairs
+
+    points = [[lon, lat] for (lon, lat) in sampled]
+    n_shown = len(points)
+    downsampled = n_shown < n_total
+
+    lons_s = [p[0] for p in sampled]
+    lats_s = [p[1] for p in sampled]
+    lon_min, lon_max = min(lons_s), max(lons_s)
+    lat_min, lat_max = min(lats_s), max(lats_s)
+    bbox = {
+        "lat_min": lat_min,
+        "lat_max": lat_max,
+        "lon_min": lon_min,
+        "lon_max": lon_max,
+    }
+
+    # Aspect for an equirectangular projection: stretch the x axis by 1/cos(lat)
+    # at the cloud centroid so a degree of longitude reads at its real width.
+    centroid_lat = sum(lats_s) / len(lats_s)
+    cos_lat = math.cos(math.radians(centroid_lat))
+    if cos_lat < 1e-12:  # centroid at (or numerically at) a pole
+        aspect = _ASPECT_MAX
+    else:
+        aspect = 1.0 / cos_lat
+    aspect = max(_ASPECT_MIN, min(_ASPECT_MAX, aspect))
+
+    # Padding ~5% of each range, with a small floor so a zero-range cloud (single
+    # point / all identical) still gets a non-zero margin.
+    pad_lon = max(0.05 * (lon_max - lon_min), _MIN_PAD)
+    pad_lat = max(0.05 * (lat_max - lat_min), _MIN_PAD)
+
+    return {
+        "points": points,
+        "n_total": n_total,
+        "n_shown": n_shown,
+        "downsampled": downsampled,
+        "bbox": bbox,
+        "aspect": aspect,
+        "pad": {"lon": pad_lon, "lat": pad_lat},
+    }

python/functions/datascience/build_geo_scatter_test.py

@@ -0,0 +1,140 @@
+"""Tests para build_geo_scatter."""
+
+import math
+import os
+import sys
+
+sys.path.insert(0, os.path.dirname(__file__))
+
+from build_geo_scatter import build_geo_scatter
+
+# Keys that a non-empty result dict must always contain.
+_EXPECTED_KEYS = {
+    "points", "n_total", "n_shown", "downsampled", "bbox", "aspect", "pad",
+}
+
+
+def test_geo_scatter_nube_espana():
+    """Golden: nube en Espana -> points en orden [lon, lat], bbox, aspect>1, pad 5%."""
+    # Cuatro puntos alrededor de Madrid (lat ~40, lon negativo).
+    lats = [40.0, 41.0, 39.0, 40.5]
+    lons = [-3.7, -3.0, -4.0, -3.5]
+    r = build_geo_scatter(lats, lons)
+
+    assert set(r.keys()) == _EXPECTED_KEYS
+
+    # points en orden [x=lon, y=lat]: primer elemento lon (negativo), segundo lat (~40).
+    assert r["points"] == [[-3.7, 40.0], [-3.0, 41.0], [-4.0, 39.0], [-3.5, 40.5]]
+    for lon, lat in r["points"]:
+        assert lon < 0.0          # longitudes de Espana son negativas
+        assert 36.0 < lat < 44.0  # latitudes peninsulares
+
+    # Sin downsampling: 4 < 2000.
+    assert r["n_total"] == 4
+    assert r["n_shown"] == 4
+    assert r["downsampled"] is False
+
+    # bbox correcto.
+    assert r["bbox"] == {
+        "lat_min": 39.0, "lat_max": 41.0,
+        "lon_min": -4.0, "lon_max": -3.0,
+    }
+
+    # aspect = 1/cos(centroid_lat); centroid = 40.125 -> ~1.31 > 1.
+    centroid_lat = (40.0 + 41.0 + 39.0 + 40.5) / 4.0
+    expected_aspect = 1.0 / math.cos(math.radians(centroid_lat))
+    assert r["aspect"] > 1.0
+    assert abs(r["aspect"] - expected_aspect) < 1e-9
+    assert abs(r["aspect"] - 1.305) < 0.02  # cos(40) ~ 0.77
+
+    # pad 5% del rango (lon_range=1.0 -> 0.05 ; lat_range=2.0 -> 0.1).
+    assert abs(r["pad"]["lon"] - 0.05) < 1e-9
+    assert abs(r["pad"]["lat"] - 0.10) < 1e-9
+
+
+def test_downsampling_determinista_y_reproducible():
+    """Golden: 5000 puntos, max_points=2000 -> n_shown<=2000, downsampled, reproducible."""
+    lats = [40.0 + (i % 100) * 0.01 for i in range(5000)]
+    lons = [-3.0 - (i % 100) * 0.01 for i in range(5000)]
+
+    r1 = build_geo_scatter(lats, lons, max_points=2000)
+
+    assert r1["n_total"] == 5000
+    assert r1["n_shown"] <= 2000
+    assert r1["downsampled"] is True
+    # step = ceil(5000/2000) = 3 -> len(pairs[::3]) = 1667.
+    assert r1["n_shown"] == 1667
+
+    # Determinista: dos llamadas con la misma entrada dan exactamente lo mismo.
+    r2 = build_geo_scatter(lats, lons, max_points=2000)
+    assert r1 == r2
+    assert r1["points"] == r2["points"]
+
+    # El primer punto del downsample es el primer par valido (step parte de 0).
+    assert r1["points"][0] == [lons[0], lats[0]]
+
+
+def test_listas_vacias_no_lanza():
+    """Edge: listas vacias / None -> points [] sin lanzar."""
+    r = build_geo_scatter([], [])
+    assert r["points"] == []
+    assert r["n_total"] == 0
+    assert r["n_shown"] == 0
+    assert r["downsampled"] is False
+    assert r["bbox"] is None
+    assert r["aspect"] == 1.0
+    assert r["pad"] == {"lon": 0.0, "lat": 0.0}
+
+    # None como entrada tampoco lanza.
+    assert build_geo_scatter(None, None)["points"] == []
+    assert build_geo_scatter([40.0], None)["n_total"] == 0
+    assert build_geo_scatter(None, [-3.0])["n_total"] == 0
+
+
+def test_un_solo_punto_pad_minimo_y_aspect_finito():
+    """Edge: un solo punto -> pad minimo no cero, bbox degenerado, aspect finito."""
+    r = build_geo_scatter([40.0], [-3.7])
+
+    assert r["n_total"] == 1
+    assert r["n_shown"] == 1
+    assert r["points"] == [[-3.7, 40.0]]
+    assert r["downsampled"] is False
+    assert r["bbox"] == {
+        "lat_min": 40.0, "lat_max": 40.0,
+        "lon_min": -3.7, "lon_max": -3.7,
+    }
+    # rango 0 -> pad cae al floor minimo (no cero).
+    assert r["pad"]["lon"] == 0.01
+    assert r["pad"]["lat"] == 0.01
+    # aspect finito y dentro del clamp.
+    assert math.isfinite(r["aspect"])
+    assert 0.3 <= r["aspect"] <= 5.0
+
+
+def test_filtra_none_nan_y_fuera_de_rango():
+    """Edge: pares con None/NaN/fuera de rango se descartan por indice."""
+    nan = float("nan")
+    inf = float("inf")
+    #          i=0     i=1   i=2   i=3      i=4     i=5      i=6
+    lats = [40.0, None, nan, 200.0, 41.0, 39.0, inf]
+    lons = [-3.0, -3.5, -3.6, -3.7, 999.0, -4.0, -2.0]
+    r = build_geo_scatter(lats, lons)
+
+    # Validos solo i=0 (40,-3.0) e i=5 (39,-4.0):
+    #   i=1 lat None, i=2 lat NaN, i=3 lat 200 fuera de rango,
+    #   i=4 lon 999 fuera de rango, i=6 lat inf.
+    assert r["n_total"] == 2
+    assert r["points"] == [[-3.0, 40.0], [-4.0, 39.0]]
+    assert r["bbox"] == {
+        "lat_min": 39.0, "lat_max": 40.0,
+        "lon_min": -4.0, "lon_max": -3.0,
+    }
+
+
+def test_latitud_alta_aspect_clamped():
+    """Edge: latitudes ~85 -> aspect clamped <= 5.0."""
+    r = build_geo_scatter([85.0, 85.0, 84.0], [10.0, 11.0, 9.0])
+    # cos(~84.7) ~ 0.093 -> 1/0.093 ~ 10.7 -> clamp a 5.0.
+    assert r["aspect"] <= 5.0
+    assert r["aspect"] == 5.0
+    assert math.isfinite(r["aspect"])

python/functions/datascience/detect_latlon_columns.md

@@ -0,0 +1,67 @@
+---
+name: detect_latlon_columns
+id: detect_latlon_columns_py_datascience
+kind: function
+lang: py
+domain: datascience
+version: "1.0.0"
+purity: pure
+signature: "def detect_latlon_columns(columns: list, samples: dict | None = None) -> dict"
+description: "Detecta un par (latitud, longitud) entre las columnas de un TableProfile del grupo eda combinando heuristica de nombre (latitude/longitude/lat/lon/lng + x/y debiles) con validacion de rango obligatoria (latitud en [-90,90], longitud en [-180,180]). Lee defensivamente con .get; NUNCA lanza. Usa el sub-bloque numeric.min/max o, si falta, la lista de samples opcional. Devuelve SIEMPRE un dict {lat_col, lon_col, confidence, reason}; si no hay par valido, las columnas van a None y confidence a 0.0."
+tags: [eda, geospatial, profiling, latlon, coordinates, detection, datascience]
+params:
+  - name: columns
+    desc: "Lista de dicts ColumnProfile (el campo `columns` de un TableProfile del grupo eda). Cada dict se lee con .get; solo `name` (str) es obligatorio. Se consultan `inferred_type` (p.ej. 'numeric') y el sub-dict `numeric` con `min`/`max` (floats) para validar el rango. Entradas no-dict o sin name se ignoran sin lanzar."
+  - name: samples
+    desc: "Opcional {nombre_columna: [valores...]} para validar el rango cuando una columna no trae numeric.min/max. Los valores nulos se ignoran; si algun valor no nulo no es numerico la columna no se considera coordenada. Si es None u omitido, solo se usa el bloque numeric."
+output: "Dict SIEMPRE presente con la forma {lat_col: str|None, lon_col: str|None, confidence: float en [0,1], reason: str en espanol}. En exito, lat_col y lon_col nombran columnas distintas; confidence ~1.0 para par con nombre fuerte (latitude/longitude/lat/lon/lng) + rango valido y ~0.7 para par debil (x/y) + rango. En fallo, ambas columnas None, confidence 0.0 y reason explica por que (sin columnas, nombre sin match, rango fuera de bounds, falta uno de los dos ejes...)."
+uses_functions: []
+uses_types: []
+returns: []
+returns_optional: false
+error_type: ""
+imports: []
+tested: true
+tests: ["test_par_latitude_longitude_fuerte", "test_par_lat_lon_abreviado", "test_par_x_y_debil_con_rango_valido", "test_nombre_lat_lon_pero_rango_fuera_no_detecta", "test_par_fuerte_prevalece_sobre_debil", "test_entradas_vacias_o_invalidas_no_lanzan", "test_solo_latitud_sin_longitud_no_detecta", "test_deteccion_por_samples_cuando_falta_numeric", "test_samples_fuera_de_rango_descarta"]
+test_file_path: "python/functions/datascience/detect_latlon_columns_test.py"
+file_path: "python/functions/datascience/detect_latlon_columns.py"
+---
+
+## Ejemplo
+
+```python
+import sys, os
+sys.path.insert(0, os.path.join("python", "functions"))
+from datascience.detect_latlon_columns import detect_latlon_columns
+
+# Columnas tal y como vienen en profile['columns'] de un TableProfile del grupo eda:
+columns = [
+    {"name": "id", "inferred_type": "numeric", "numeric": {"min": 1, "max": 9999}},
+    {"name": "latitude", "inferred_type": "numeric", "numeric": {"min": -45.0, "max": 45.0}},
+    {"name": "longitude", "inferred_type": "numeric", "numeric": {"min": -120.0, "max": 120.0}},
+]
+res = detect_latlon_columns(columns)
+print(res["lat_col"], res["lon_col"], res["confidence"])
+# latitude longitude 1.0
+
+# Sin bloque numeric, validando el rango con samples:
+cols2 = [{"name": "lat"}, {"name": "lon"}]
+samples = {"lat": [10.5, 20.0, 30.25], "lon": [-40.0, 50.5, 60.0]}
+print(detect_latlon_columns(cols2, samples)["lat_col"])  # lat
+```
+
+## Cuando usarla
+
+- Usala al perfilar una tabla en `AutomaticEDA` para decidir si tiene geometria de puntos: cuando `detect_latlon_columns` devuelve un par con `confidence` alta, el capitulo geospatial puede dibujar un mapa, calcular un bounding box o proponer un cluster espacial.
+- Antes de un analisis geoespacial (alpha shape, convex hull, joins por proximidad) para localizar automaticamente que columnas son la latitud y la longitud sin pedirlo al usuario.
+- Cuando recibas un `TableProfile` del grupo `eda` y quieras enrutar columnas a sub-analisis por tipo semantico: este es el detector del par lat/lon, complementario a `infer_semantic_type`.
+
+## Gotchas
+
+- Funcion pura, sin I/O y determinista. Lectura defensiva con `.get`: NUNCA lanza. Cualquier input malformado (None, no-lista, entradas no-dict, claves ausentes) devuelve el dict de fallo con `lat_col`/`lon_col` en None y `confidence` 0.0.
+- **El nombre solo no basta**: una columna `latitude` cuyo rango se sale de `[-90, 90]` se descarta (no es coordenada real). Igual para `longitude` fuera de `[-180, 180]`. La validacion de rango es obligatoria.
+- El rango de latitud `[-90, 90]` es un subconjunto del de longitud `[-180, 180]`, por eso el nombre es necesario para desambiguar cual eje es cual; una columna numerica en `[-90, 90]` sin nombre que sugiera lat/lon no se detecta.
+- Los nombres genericos `x`/`y` (y `x_coord`/`y_coord`) son candidatos **debiles**: solo forman par si el rango encaja y existe la otra mitad (un `x`/`lon` para la `y`, un `y`/`lat` para la `x`). Un `y` suelto sin pareja devuelve None.
+- Requiere AMBOS ejes para considerar exito. Si solo encuentra latitud o solo longitud, devuelve el dict de fallo (no media coordenada).
+- `samples` solo se consulta cuando falta `numeric.min`/`numeric.max`. Si una columna trae el bloque numeric, ese manda aunque pases samples para ella.
+- El matching de nombre es por subcadena normalizada (se quitan `_`, `-` y espacios), asi que nombres como `plate` (contiene "lat") podrian marcarse como candidatos por nombre — pero solo pasarian si su rango cae en `[-90, 90]` y hay una longitud pareja, filtro que en la practica descarta los falsos positivos.

python/functions/datascience/detect_latlon_columns.py

@@ -0,0 +1,198 @@
+"""detect_latlon_columns — detect a (latitude, longitude) column pair in an EDA profile.
+
+Pure function: no I/O, deterministic. Takes the `columns` list of a TableProfile
+(group `eda`) and decides whether two of its columns form a geographic coordinate
+pair (latitude + longitude), combining a name heuristic with a value-range check.
+
+The detection is intentionally conservative: a name hint alone is never enough. A
+column is only accepted as latitude/longitude if its numeric range fits inside the
+valid coordinate bounds ([-90, 90] for latitude, [-180, 180] for longitude). When
+the `numeric` sub-block is absent the optional `samples` argument is used instead.
+
+Reading is fully defensive (.get throughout) and the function NEVER raises: any
+malformed input (None, non-list, non-dict entries, missing keys) simply yields a
+no-pair result {"lat_col": None, "lon_col": None, "confidence": 0.0, "reason": ...}.
+"""
+
+import re
+
+# Collapse the separators a column name may use (snake_case, kebab-case, spaces)
+# so that "y_coord", "y-coord" and "y coord" all normalize to the same token.
+_SEP_RE = re.compile(r"[\s_\-]+")
+
+# Name-match strengths: a strong, unambiguous coordinate name vs a weak generic
+# axis name (x / y) that only counts when the range also fits and a partner exists.
+_STRONG = 0.6
+_WEAK = 0.3
+_RANGE_BONUS = 0.4  # added once the mandatory range validation passes
+
+
+def _normalize(name):
+    """Lowercase a column name and strip separator chars (_, -, whitespace)."""
+    if not isinstance(name, str):
+        return ""
+    return _SEP_RE.sub("", name.strip().lower())
+
+
+def _num(value):
+    """Coerce to float defensively; return None for None/bool/non-numeric."""
+    # bool is a subclass of int; a coordinate value is never a real bool, so treat
+    # True/False as missing instead of silently coercing to 1.0/0.0.
+    if value is None or isinstance(value, bool):
+        return None
+    try:
+        return float(value)
+    except (TypeError, ValueError):
+        return None
+
+
+def _lat_name_strength(nn):
+    """Strength of a normalized name as a latitude candidate (0=no match)."""
+    if not nn:
+        return 0.0
+    # "lat", "latitude", "latitud" all contain the "lat" stem.
+    if "lat" in nn:
+        return _STRONG
+    # Weak generic axis name: only useful when paired with an x/lon partner.
+    if nn in ("y", "ycoord", "ycoordinate", "ycoordinates"):
+        return _WEAK
+    return 0.0
+
+
+def _lon_name_strength(nn):
+    """Strength of a normalized name as a longitude candidate (0=no match)."""
+    if not nn:
+        return 0.0
+    # "lon", "long", "longitude", "longitud" share the "lon" stem; "lng" is separate.
+    if "lon" in nn or "lng" in nn:
+        return _STRONG
+    if nn in ("x", "xcoord", "xcoordinate", "xcoordinates"):
+        return _WEAK
+    return 0.0
+
+
+def _col_range(col, sample_values):
+    """Return (min, max) floats for a column, or (None, None) if not numeric.
+
+    Prefers the `numeric` sub-block min/max (the output of describe_numeric); falls
+    back to the provided sample list. A column is only treated as numeric when both
+    extremes are derivable: from the numeric block, or from samples whose every
+    non-null value coerces to a number.
+    """
+    if isinstance(col, dict):
+        numeric = col.get("numeric")
+        if isinstance(numeric, dict):
+            mn = _num(numeric.get("min"))
+            mx = _num(numeric.get("max"))
+            if mn is not None and mx is not None:
+                return mn, mx
+    # Fall back to samples when the numeric block is missing or incomplete.
+    if isinstance(sample_values, (list, tuple)):
+        non_null = [v for v in sample_values if v is not None]
+        if non_null:
+            coerced = [_num(v) for v in non_null]
+            # Any non-numeric sample means we cannot trust the column as numeric.
+            if all(c is not None for c in coerced):
+                return min(coerced), max(coerced)
+    return None, None
+
+
+def _no_pair(reason):
+    """Canonical empty result: no coordinate pair detected."""
+    return {"lat_col": None, "lon_col": None, "confidence": 0.0, "reason": reason}
+
+
+def detect_latlon_columns(columns: list, samples: dict | None = None) -> dict:
+    """Detect a (latitude, longitude) column pair from an eda TableProfile.
+
+    Combines a name heuristic (latitude/longitude/lat/lon/lng + weak x/y) with a
+    mandatory range validation: the chosen latitude must sit in [-90, 90] and the
+    longitude in [-180, 180]. A name hint whose range does not fit is discarded.
+    Both sides are required for success; if only one is found, no pair is returned.
+
+    Args:
+        columns: List of ColumnProfile dicts (the `columns` of a TableProfile).
+            Each dict is read defensively with .get; only `name` is required.
+            `numeric.min` / `numeric.max` (and optionally `inferred_type`) are used
+            for the range check when present.
+        samples: Optional {column_name: [values...]} used to validate the range
+            when a column lacks `numeric.min`/`numeric.max`. If None/omitted, only
+            the `numeric` sub-block is consulted.
+
+    Returns:
+        Always a dict {"lat_col": str|None, "lon_col": str|None,
+        "confidence": float, "reason": str}. On success lat_col and lon_col name
+        the detected pair (distinct columns) and confidence is in [0, 1]: a pair
+        validated by a strong name on both sides scores ~1.0, a weak x/y pair ~0.7.
+        On failure both columns are None and confidence is 0.0.
+    """
+    if not isinstance(columns, (list, tuple)) or len(columns) == 0:
+        return _no_pair("sin columnas que inspeccionar")
+
+    sample_map = samples if isinstance(samples, dict) else {}
+
+    # (column_name, confidence) for each side. Confidence already includes the
+    # range bonus because membership in the list implies the range was validated.
+    lat_candidates = []
+    lon_candidates = []
+
+    for col in columns:
+        if not isinstance(col, dict):
+            continue
+        name = col.get("name")
+        if not isinstance(name, str) or not name:
+            continue
+
+        nn = _normalize(name)
+        lat_strength = _lat_name_strength(nn)
+        lon_strength = _lon_name_strength(nn)
+        if lat_strength == 0.0 and lon_strength == 0.0:
+            continue  # name gives no coordinate hint; skip.
+
+        mn, mx = _col_range(col, sample_map.get(name))
+        is_numeric = mn is not None and mx is not None
+        if not is_numeric:
+            continue  # range cannot be validated -> not a coordinate.
+
+        if lat_strength > 0.0 and mn >= -90.0 and mx <= 90.0:
+            lat_candidates.append((name, lat_strength + _RANGE_BONUS))
+        if lon_strength > 0.0 and mn >= -180.0 and mx <= 180.0:
+            lon_candidates.append((name, lon_strength + _RANGE_BONUS))
+
+    if not lat_candidates and not lon_candidates:
+        return _no_pair("ninguna columna sugiere latitud ni longitud por nombre+rango")
+    if not lat_candidates:
+        return _no_pair("no se encontro columna de latitud valida (nombre+rango en [-90,90])")
+    if not lon_candidates:
+        return _no_pair("no se encontro columna de longitud valida (nombre+rango en [-180,180])")
+
+    # Pick the distinct pair with the highest combined confidence. First match wins
+    # on ties to keep the result deterministic by input order.
+    best = None  # (combined, lat_name, lon_name, lat_c, lon_c)
+    for lat_name, lat_c in lat_candidates:
+        for lon_name, lon_c in lon_candidates:
+            if lat_name == lon_name:
+                continue  # a column cannot be both axes of the same pair.
+            combined = (lat_c + lon_c) / 2.0
+            if best is None or combined > best[0]:
+                best = (combined, lat_name, lon_name, lat_c, lon_c)
+
+    if best is None:
+        return _no_pair("solo una columna sirve para ambos ejes; no hay par lat/lon distinto")
+
+    combined, lat_name, lon_name, lat_c, lon_c = best
+    confidence = max(0.0, min(1.0, combined))
+
+    lat_label = "fuerte" if lat_c >= 0.9 else "debil"
+    lon_label = "fuerte" if lon_c >= 0.9 else "debil"
+    reason = (
+        f"par lat='{lat_name}' (nombre {lat_label}) / lon='{lon_name}' "
+        f"(nombre {lon_label}) con rango valido"
+    )
+
+    return {
+        "lat_col": lat_name,
+        "lon_col": lon_name,
+        "confidence": confidence,
+        "reason": reason,
+    }

python/functions/datascience/detect_latlon_columns_test.py

@@ -0,0 +1,141 @@
+"""Tests para detect_latlon_columns."""
+
+import os
+import sys
+
+sys.path.insert(0, os.path.dirname(__file__))
+
+from detect_latlon_columns import detect_latlon_columns
+
+# Keys that every result dict (success or failure) must expose.
+_EXPECTED_KEYS = {"lat_col", "lon_col", "confidence", "reason"}
+
+
+def _col(name, mn=None, mx=None, inferred="numeric"):
+    """Build a minimal ColumnProfile-like dict for the tests."""
+    col = {"name": name, "inferred_type": inferred}
+    if mn is not None or mx is not None:
+        col["numeric"] = {"min": mn, "max": mx}
+    return col
+
+
+def test_par_latitude_longitude_fuerte():
+    """Golden: nombres latitude/longitude con rango valido -> par con confianza alta."""
+    columns = [
+        _col("id", mn=1, mx=9999, inferred="numeric"),
+        _col("latitude", mn=-45.0, mx=45.0),
+        _col("longitude", mn=-120.0, mx=120.0),
+    ]
+    res = detect_latlon_columns(columns)
+
+    assert set(res.keys()) == _EXPECTED_KEYS
+    assert res["lat_col"] == "latitude"
+    assert res["lon_col"] == "longitude"
+    # Nombre fuerte (0.6) + rango (0.4) en ambos lados -> 1.0.
+    assert abs(res["confidence"] - 1.0) < 1e-9
+    assert "rango valido" in res["reason"]
+
+
+def test_par_lat_lon_abreviado():
+    """Golden: nombres abreviados lat/lon tambien se detectan como fuertes."""
+    columns = [
+        _col("lat", mn=40.0, mx=43.0),
+        _col("lon", mn=-4.0, mx=-1.0),
+        _col("precio", mn=0.0, mx=500.0),
+    ]
+    res = detect_latlon_columns(columns)
+    assert res["lat_col"] == "lat"
+    assert res["lon_col"] == "lon"
+    assert abs(res["confidence"] - 1.0) < 1e-9
+
+
+def test_par_x_y_debil_con_rango_valido():
+    """Edge: x/y genericos solo cuentan como par debil cuando el rango encaja."""
+    columns = [
+        _col("y_coord", mn=-10.0, mx=10.0),   # debil latitud
+        _col("x_coord", mn=-150.0, mx=150.0),  # debil longitud
+    ]
+    res = detect_latlon_columns(columns)
+    assert res["lat_col"] == "y_coord"
+    assert res["lon_col"] == "x_coord"
+    # Nombre debil (0.3) + rango (0.4) -> 0.7 en ambos lados.
+    assert abs(res["confidence"] - 0.7) < 1e-9
+
+
+def test_nombre_lat_lon_pero_rango_fuera_no_detecta():
+    """Edge: nombre lat/lon con rango fuera de bounds -> NO es coordenada."""
+    columns = [
+        _col("latitude", mn=-200.0, mx=200.0),   # fuera de [-90, 90]
+        _col("longitude", mn=-120.0, mx=120.0),  # valido, pero sin par lat
+    ]
+    res = detect_latlon_columns(columns)
+    assert res["lat_col"] is None
+    assert res["lon_col"] is None
+    assert res["confidence"] == 0.0
+    assert isinstance(res["reason"], str) and res["reason"]
+
+
+def test_par_fuerte_prevalece_sobre_debil():
+    """Edge: con candidatos fuertes y debiles, gana el par de mayor confianza."""
+    columns = [
+        _col("latitude", mn=-45.0, mx=45.0),    # fuerte lat
+        _col("y", mn=-30.0, mx=30.0),           # debil lat
+        _col("longitude", mn=-120.0, mx=120.0),  # fuerte lon
+        _col("x", mn=-100.0, mx=100.0),         # debil lon
+    ]
+    res = detect_latlon_columns(columns)
+    assert res["lat_col"] == "latitude"
+    assert res["lon_col"] == "longitude"
+    assert abs(res["confidence"] - 1.0) < 1e-9
+
+
+def test_entradas_vacias_o_invalidas_no_lanzan():
+    """Edge: sin columnas / vacio / no-lista / entradas no-dict -> dict None sin lanzar."""
+    for bad in ([], None, "no soy lista", 42, [1, 2, 3], [{}], [{"foo": "bar"}]):
+        res = detect_latlon_columns(bad)
+        assert set(res.keys()) == _EXPECTED_KEYS
+        assert res["lat_col"] is None
+        assert res["lon_col"] is None
+        assert res["confidence"] == 0.0
+        assert isinstance(res["reason"], str)
+
+
+def test_solo_latitud_sin_longitud_no_detecta():
+    """Edge: solo hay latitud valida, falta la longitud -> sin par."""
+    columns = [
+        _col("latitude", mn=-45.0, mx=45.0),
+        _col("temperatura", mn=-5.0, mx=40.0),
+    ]
+    res = detect_latlon_columns(columns)
+    assert res["lat_col"] is None
+    assert res["lon_col"] is None
+    assert res["confidence"] == 0.0
+
+
+def test_deteccion_por_samples_cuando_falta_numeric():
+    """Edge: sin bloque numeric, el rango se valida con samples."""
+    columns = [
+        {"name": "lat"},  # sin numeric ni inferred_type
+        {"name": "lon"},
+    ]
+    samples = {
+        "lat": [10.5, 20.0, None, 30.25],   # todos dentro de [-90, 90]
+        "lon": [-40.0, 50.5, 60.0],          # todos dentro de [-180, 180]
+    }
+    res = detect_latlon_columns(columns, samples)
+    assert res["lat_col"] == "lat"
+    assert res["lon_col"] == "lon"
+    assert abs(res["confidence"] - 1.0) < 1e-9
+
+
+def test_samples_fuera_de_rango_descarta():
+    """Edge: samples fuera de bounds invalidan la columna pese al nombre fuerte."""
+    columns = [{"name": "lat"}, {"name": "lon"}]
+    samples = {
+        "lat": [10.0, 95.0],   # 95 > 90 -> latitud invalida
+        "lon": [-40.0, 50.0],
+    }
+    res = detect_latlon_columns(columns, samples)
+    assert res["lat_col"] is None
+    assert res["lon_col"] is None
+    assert res["confidence"] == 0.0