github.com/apache/beam/sdks/v2@v2.48.2/python/apache_beam/examples/snippets/transforms/aggregation/min.py (about)

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    18  
    19  
    20  def min_globally(test=None):
    21    # [START min_globally]
    22    import apache_beam as beam
    23  
    24    with beam.Pipeline() as pipeline:
    25      min_element = (
    26          pipeline
    27          | 'Create numbers' >> beam.Create([3, 4, 1, 2])
    28          | 'Get min value' >>
    29          beam.CombineGlobally(lambda elements: min(elements or [-1]))
    30          | beam.Map(print))
    31      # [END min_globally]
    32      if test:
    33        test(min_element)
    34  
    35  
    36  def min_per_key(test=None):
    37    # [START min_per_key]
    38    import apache_beam as beam
    39  
    40    with beam.Pipeline() as pipeline:
    41      elements_with_min_value_per_key = (
    42          pipeline
    43          | 'Create produce' >> beam.Create([
    44              ('🥕', 3),
    45              ('🥕', 2),
    46              ('🍆', 1),
    47              ('🍅', 4),
    48              ('🍅', 5),
    49              ('🍅', 3),
    50          ])
    51          | 'Get min value per key' >> beam.CombinePerKey(min)
    52          | beam.Map(print))
    53      # [END min_per_key]
    54      if test:
    55        test(elements_with_min_value_per_key)