**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 the two scalar input signals are not equal. 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. Comparing constants**

Consider a variable *y* such that:

If* t* ≠ 0.5 then *y* = cos(*t*); else
*y* = 0

where *t *is simulation time realized as:

Until the value of *t* reaches 0.5, the
Boolean inequality *t* ≠ 0.5 evaluates to true, and *y* takes on a value of
cos(*t*). At *t* = 0.5 sec, the Boolean inequality evaluates to false,
and at the very next time step, returns to true, and remains true for the
duration of the simulation. Consequently, at the moment *t* = 0.5 sec,
*y* takes on the value of 0, and at every other point, *y* is equal to
cos(*t*).