A Step function (

) is a sharp transition from 
0 to some other value (amplitude) at some location (a certain time, for example). Create a single step function with a certain amplitude from an initial level to a final level at a start location. The step function is a function of one variable (the time 
t, for example). The default 
Function name is 
step1.
 
    Enter a Location (
s0) for the start of the step. The value of the step function is the start level for input values that are smaller than the location of the step. In the 
From field, enter a start level (
Lstart ). In the 
To field, enter a final level (
Lend). For an input variable 
s, a start location 
s0, a start level 
Lstart, and a final level 
Lend, the step function’s value is 
Lstart for 
s < s0 and 
Lend for 
s ≥ s0. The amplitude of the step is 
Lend −  Lstart. You can use unit syntax to assign units to these parameters.