In the Test Sequence block, you can generate signals for testing.

Define an output data symbol in the

**Data Symbols**pane.Use the output name with a signal generation function in the test step action.

You can call external functions from the Test Sequence block. Define a
function in a script on the MATLAB^{®} path, and call the function in the test sequence.

This example shows how to produce a sine and a random number test signal in a Test Sequence block.

The step `Sine`

outputs a sine wave with a period of 10 seconds, specified by the argument `et*2*pi/10`

. The step `Random`

outputs a random number in the interval `-0.5 to 0.5`

.

The test sequence produces signal `sg`

.

This example shows how to call an externally-defined function from the Test Sequence block. Define a function in a script on the MATLAB® path, and call the function from the test sequence.

In this example, the step `ReducedSine`

reduces the signal `sg`

using the function `Attenuate`

.

The test sequence produces signal `sg`

and attenuated signal `asg`

.

Some signal generation functions use the temporal operator `et`

, which is the
elapsed time of the test step in seconds. Scaling, rounding, and other approximations of
argument values can affect function outputs. Common
signal generation functions include:

Function | Syntax | Description | Example |
---|---|---|---|

square | `square(x)` | Represents a square wave output with a period of Within
the interval | Output a square wave with a period of square(et/10) |

sawtooth | `sawtooth(x)` | Represents a sawtooth wave output with a period of Within
the interval | Output a sawtooth wave with a period of sawtooth(et/10) |

triangle | `triangle(x)` | Represents a triangle wave output with a period of Within
the interval | Output a triangle wave with a period of triangle(et/10) |

ramp | `ramp(x)` | Represents a ramp signal of slope
| Ramp one unit for every 5 seconds of test step elapsed time: ramp(et/5) |

heaviside | `heaviside(x)` | Represents a heaviside step signal, returning | Output a heaviside signal after heaviside(et-5) |

latch | `latch(x)` | Saves the value of | Latch b = latch(torque) |

`sin` | `sin(x)` | Returns the sine of | A sine wave with a period of 10 sec: sin(et*2*pi/10) |

`cos` | `cos(x)` | Returns the cosine of | A cosine wave with a period of 10 sec: cos(et*2*pi/10) |

`rand` | `rand` | Uniformly distributed pseudorandom values | Generate new random values for each simulation by declaring ```
coder.extrinsic('rand')
nr = rand
sg = a + (b-a)*nr
``` |

`randn` | `randn` | Normally distributed pseudorandom values |
Generate new random values for each simulation by declaring
```
coder.extrinsic('randn')
nr = randn
sg = nr*2
``` |

`exp` | `exp(x)` | Returns the natural exponential function, $${e}^{x}$$. | An exponential signal progressing at one tenth of the test step elapsed time: exp(et/10) |

Test Sequence | Test Sequence and Assessment Syntax