What is a "scalar" variable in Spatial Modeler?
The "scalar" is used as a single variable that may be included in several functions in the model.
Lets say that you have five functions in a model, each with a particular value (e.g., 2) at three places within the function. You can either type the value "2" in the functions or tie the scalar variable to each function and insert the variable in the statement (in place of the value 2). The advantage to using the scalar variable is that if you want to change the value from, say, 2 to 3, you only have to change it once in the scalar dialog instead of fifteen times in five different functions.