Source code for EvaluateFitness.EvalVarMaxFitness

 1"""Variance-based (signal activity) fitness evaluator.
 2
 3Fitness equals the mean absolute difference between consecutive waveform
 4samples, rewarding circuits that produce high-activity signals. Used with
 5:class:`~EvaluateFitness.EvaluateFitness.EvaluateFitness` via the
 6:class:`~EvaluateFitness.EvaluateFitness.FitnessEvaluator` protocol::
 7
 8    evaluator = EvalVarMaxFitness(plot_data_recorder=recorder)
 9    EvaluateFitness(evaluator)
10"""
11
12from PlotDataRecorder import PlotDataRecorder
13
14

[docs]
15class EvalVarMaxFitness:
16    """Evaluate fitness by measuring sequential voltage variance in a waveform.
17
18    Tracks the best waveform per generation for heatmap recording.
19    """
20

[docs]
21    def __init__(self, plot_data_recorder: PlotDataRecorder):
22        """Create an evaluator that records live data to *plot_data_recorder*."""
23        self.__plot_data_recorder = plot_data_recorder
24        self.__best_waveform = []
25        self.__best_waveform_fit = 0
26        self.__epoch = 0

27

[docs]
28    def start_eval(self):
29        """Reset per-generation best waveform tracking."""
30        self.__best_waveform = []
31        self.__best_waveform_fit = 0

32

[docs]
33    def end_eval(self):
34        """Record the best waveform of this generation and advance the epoch counter."""
35        self.__plot_data_recorder.record_waveform_heatmap(self.__epoch, self.__best_waveform)
36        self.__epoch += 1

37

[docs]
38    def calculate_success(self, data: list[int], index: int, src_pop: str) -> float:
39        """Compute variance-based fitness from a waveform in *data*."""
40        waveform = data
41        variance_sum = 0
42        total_samples = len(waveform)
43        for i in range(len(waveform)-1):
44            # NOTE Signal Variance is calculated by summing the absolute difference of
45            # sequential voltage samples from the microcontroller.
46            # Capture the next point in the data file to a variable
47            initial1 = waveform[i]
48            # Capture the next point + 1 in the data file to a variable
49            initial2 = waveform[i+1]
50            # Take the absolute difference of the two points and store to a variable
51            variance = abs(initial2 - initial1)
52
53            if initial1 != None and initial1 < 1000:
54                variance_sum += variance
55
56        fitness = variance_sum / total_samples
57
58        if fitness > self.__best_waveform_fit:
59            self.__best_waveform_fit = fitness
60            self.__best_waveform = waveform
61
62        self.__plot_data_recorder.record_waveform(waveform)
63        self.__plot_data_recorder.record_all_live_data(index, fitness, src_pop)
64
65        return fitness

66

[docs]
67    def calculate_error(self, err: Exception, index: int, src_pop: str) -> float:
68        """Return zero fitness when measurement fails."""
69        self.__plot_data_recorder.record_all_live_data(index, 0, src_pop)
70        return 0