There may be times when you will want to change the symbology of a layer in a map document. This can be accomplished through the use of the
UpdateLayer() function, which can be used to change the symbology of a layer as well as various properties of a layer. In this recipe, you will use the UpdateLayer() function to update the symbology of a layer.
The arcpy.mapping module also gives you the capability of updating layer symbology from your scripts by using the UpdateLayer() function. For example, you might want your script to update a layer's symbology from a graduated color to a graduated symbol, as illustrated in the following screenshot. UpdateLayer() can also be used to update various layer properties, but the default functionality is to update the symbology. Since UpdateLayer() is a robust function that is capable of altering both symbology and properties, you do need to understand the various parameters that can be supplied as an input:
