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# Coordinate Transformations
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Functions for transforming coordinates and geometries between different coordinate reference systems, essential for integrating data from different sources and projections.
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## Capabilities
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### Coordinate Transformation
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Transform coordinate sequences between coordinate reference systems.
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```python { .api }
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def transform(src_crs, dst_crs, xs, ys):
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    """
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    Transform coordinate sequences between CRS.
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    Parameters:
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    - src_crs: CRS or CRS-like, source coordinate reference system
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    - dst_crs: CRS or CRS-like, destination coordinate reference system  
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    - xs: array-like, x coordinates (longitude or easting)
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    - ys: array-like, y coordinates (latitude or northing)
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    Returns:
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    tuple: (transformed_xs, transformed_ys) coordinate arrays
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    Raises:
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    - TransformError: If transformation fails
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    """
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```
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### Geometry Transformation
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Transform geometry objects between coordinate reference systems.
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```python { .api }
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def transform_geom(src_crs, dst_crs, geom, antimeridian_cutting=False, antimeridian_offset=10.0, precision=-1):
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    """
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    Transform geometry objects between CRS.
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    Parameters:
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    - src_crs: CRS or CRS-like, source coordinate reference system
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    - dst_crs: CRS or CRS-like, destination coordinate reference system
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    - geom: dict, GeoJSON-like geometry object
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    - antimeridian_cutting: bool, cut geometries at antimeridian
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    - antimeridian_offset: float, offset for antimeridian cutting
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    - precision: int, coordinate precision (-1 for no rounding)
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    Returns:
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    dict: Transformed GeoJSON-like geometry
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    Raises:
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    - TransformError: If transformation fails
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    """
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```
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#### Usage Examples
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```python
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from fiona.transform import transform, transform_geom
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from fiona.crs import CRS
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# Transform coordinate arrays
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src_crs = CRS.from_epsg(4326)  # WGS84
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dst_crs = CRS.from_epsg(32610)  # UTM Zone 10N
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# San Francisco coordinates in WGS84
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lons = [-122.4194]
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lats = [37.7749]
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# Transform to UTM
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x_utm, y_utm = transform(src_crs, dst_crs, lons, lats)
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print(f"UTM coordinates: {x_utm[0]:.2f}, {y_utm[0]:.2f}")
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# Transform geometry objects
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point_geom = {
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    'type': 'Point',
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    'coordinates': [-122.4194, 37.7749]
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}
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transformed_point = transform_geom(src_crs, dst_crs, point_geom)
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print(f"Transformed point: {transformed_point}")
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# Transform complex geometries
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polygon_geom = {
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    'type': 'Polygon',
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    'coordinates': [[
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        [-122.5, 37.7], [-122.4, 37.7], 
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        [-122.4, 37.8], [-122.5, 37.8], 
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        [-122.5, 37.7]
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    ]]
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}
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transformed_polygon = transform_geom(src_crs, dst_crs, polygon_geom)
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```