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Evaluates expressions on each cell in a raster, such as algebraic operations or conditional statements.

Input Ports

Features are input through ports A and B. The cardinality of the input is required to be one of the following cases:

  • one or more As, no Bs
  • one A, one or more Bs

Note that the B port is only visible if Two Rasters is specified in the Mode parameter.

When both A and B features are provided, the single A input will be paired with each B input.

Note the following restrictions on input features:

  • Input features must have raster geometry.
  • All paired rasters must have the same number of rows and columns.
  • Either all bands used in the same expression must have the same nodata value, or all bands used in the same expression must have no nodata value.
  • No band may have a palette.

Output Ports


Usage Notes

Note that when converting between different data types, a Bounded Cast is used. As a result, when a calculated value does not fit in the specified destination interpretation, the corresponding destination value will either be set to the minimum or maximum value possible in the destination data type.

Editing Transformer Parameters

Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click beside the applicable parameter. For more information, see Transformer Parameter Menu Options.

Transformer Categories


FME Licensing Level

FME Professional edition and above

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