**Block Category:**
Boolean

**Inputs:** Real, complex, or fixed-point scalars, or
vectors or matrices.

On the input connector tabs, “l” represents the
*x*_{1} and “r” represents the *x*_{2}.

**Description:** The >= block produces an output
signal of 1 if and only if input signal *x*_{1} is greater than or
equal to input signal *x*_{2}. Otherwise, the output is 0. On the
connector tabs, “l” represents *x*_{1} and “r” represents
*x*_{2}.

Right-click the >= block to assign a different function to the block.

**1. Simple if-then-else construct**

Consider a variable *y* such that:

If* x* ≥ 0.5 then *y* = sin(*t*); else y =
1

where *t *is simulation time. Let *x* be a unit
step delayed by 3 sec. This is usually represented as *u*(*t *- 3).
This system is realized as:

Until the onset of the step input at *t* = 3
sec, the Boolean inequality *x* ≥ 0.5 evaluates to false
and *y* takes on a value of 1. At *t* = 3 sec, the Boolean inequality
evaluates to true and remains true for the duration of the simulation duration.
Consequently, from this point onwards, *y* takes on the value of
sin(*t*).