The Switch SOP switches between up to 9999 possible inputs. The output of this SOP is specified by the Select Input field. This is useful for switching the output between several inputs depending on the evaluation of an expression placed in the Select Input field.
/input - The index of the source to use, where the first source is 0, the second 1, and so on.
Multiple SOP inputs - Several SOPs are connected to the input.
Below are two expressions that could be entered in the Select Input field:
$F-1- The first input is selected at frame 1, the second at frame 2, etc.
$F > 5- The first input is selected for the first five frames, then the second for the remaining frames.