Basic Examples (2) 

Run a cellular automaton with a random perturbation for 2 steps, here the first cell of the second row is flipped to 0:

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Specify that same perturbation:

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Scope (7) 

See the differences based on the perturbation above:

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Draw an arrow to the perturbed cell:

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Do two random perturbations:

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Visualize it:

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Use those same perturbation locations but set them both to white:

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Do a range of three perturbations at timestep two:

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Visualize it:

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Perturb the third cell at timestep one and two:

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Visualize it:

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Perturb a random sample of three at the second timestep:

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Visualize it:

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Perturb the last cell at every timestep:

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With larger k-values, you can use "AddValue" for the bit specification to make a deterministic change. Here yellow always gets flipped to white:

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Options (2) 

Setting "ReturnPerturbations" to False makes it so that only evolution of the automata is returned:

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Setting "Body" to true makes it so that the specified index is interpreted as the index within the non-zero range of the automata:

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Applications (5) 

Evolve a rule with perturbations:

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Plotting our robust automaton:

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Ten sample perturbations:

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Plot the lifetime distribution of one thousand different random single perturbations:

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Obtain the mortality curve:

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Possible Issues (3) 

When you specify an index outside the range of the body, an empty perturbation is returned:

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The tspec uses the same indexing as in CellularAutomaton, so the initial row is perturbed using zero:

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Because the automata are stitched together, using All or Automatic as an xspec is not allowed. If no xspec is given, or All or Automatic are given, xspec defaults to {-25,25}:

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Doing many perturbations sometimes results in the body dying out, with no perturbations left to perform:

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Running the function on an empty list or association returns the unperturbed cellular automaton:

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Neat Examples (3) 

Rules that "age" are particularly robust to perturbations:

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They can also be healed easily. Here we apply a therapeutic perturbation:

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With random perturbations you can see the beginning of self-reproduction in very simple rules:

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