How to extract in a shape the largest polygon each time an attribute changes value ?

Hi @pedro

You can use the transformer StatisticCalculator to extract the max value:

Thanks,

Danilo

Hi @pedro, alternatively, if the attribute 'surface' stores the area of the polygon, you can sort the features by 'surface' descending with the Sorter and then sample the first feature for each 'nom' group with the Sampler (Group By: nom, Sampling Rate (N): 1, Sampliing Type: First N Features). The DuplicateFilter (Key Attributes: nom) can also be used instead of the Sampler.