A deprecated raster function is a function that has been replaced by other functions. The function remains in ArcGIS Pro, but no further development is performed on it.
Deprecation process
Raster functions are deprecated when Esri develops a new function that provides the same capability in a better way. User feedback is instrumental in the development of new functions. Esri does not take the decision to deprecate a function lightly; the replacement must be superior to the one being deprecated. The documentation for the deprecated function also contains information about the replacement function.
In the initial release when a function is deprecated, a note will be added to the help indicating that the function is being deprecated and will encourage you to migrate to alternative methods. A message will also appear in the raster function dialog box.
One to three releases after the initial deprecation stage, a deprecated function will become fully deprecated. Existing function models can still be run, but the function is no longer accessible in the Raster Functions pane. You are encouraged to migrate to alternative methods. The documentation for the function is no longer visible in the table of contents in the help and can only be accessed through the topic URL. The documentation is preserved to maintain existing links to the tool topics.
Long-term support for deprecated raster functions
Deprecated raster functions are typically included with every version of ArcGIS Pro, so your existing raster function models will continue to work. However, if technical circumstances occur that make it impossible to include a deprecated function, the function will be removed from the installation.
Distance (Legacy) raster functions
The Distance (Legacy) raster functions are deprecated in ArcGIS Pro 3.1. See Migration from legacy distance functions to distortion-free distance functions to learn about the mapping between the previous functions and their replacements.