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(Impala)

The impala, classified as Aepyceros melampus, belongs to the family Bovidae of the order Artiodactyla. It is a slightly built African antelope that ranges from Kenya south to South Africa.

Impalas inhabit the edges of forests within reach of water, grazing on plains grasses and browsing on shrubs in the forests, where they take refuge. 

When frightened, impalas scatter, making leaps as long as 9 m (30 ft) and as high as 3 m (10 ft), which have the effect of startling and confusing lions and wild dogs, their main predators.

Only male impalas have horns, which are long, black, and of a graceful lyre shape. 

(Impala) is also the name of a mode of Symbulator. It consists in a routine embedded in the code of step# files of Symbulator, which makes the program 'fly' above a certain kind of circuits, instead of trying to run through them.

The circuits in which (Impala) is activated are those with sources as functions of time.

The source 9*sin(t) in Example A04, or the source 10*exp(-t)*sin(2*t+Pi/6) in Advanced Example F01, are both good examples of this kind of sources.

When the Symbulator is asked to solve one of these circuits, the (Impala) wakes up, and replaces the value of the complicated source by a nickname. In this step, the display says: "(Impala) Running".

After the complicated source have been replaced, the Symbulator can solve the set of equations much easier, because the equations set doesn't contain those big algebraic expressions which would be generated by the complicated source. In this step, the display says: "(Impala) Flying".

After the equations have been easily solved, the (Impala) replaces the nickname of the complicated source by the Laplace transform of its original value. It does that in every answer the Symbulator provided. In this step, the display says: "(Impala) Landing".

In circuits without this kind of complicated time-dependant sources, the (Impala) has no roll to play. In this case, the display says nothing. The (Impala) is sleeping!