2 files changed, 50 insertions, 1 deletions
diff --git a/src/argaze/GazeAnalysis/CoefficientK.py b/src/argaze/GazeAnalysis/CoefficientK.py
new file mode 100644
index 0000000..724faac
--- /dev/null
+++ b/src/argaze/GazeAnalysis/CoefficientK.py
@@ -0,0 +1,49 @@
+#!/usr/bin/env python
+
+from typing import TypeVar, Tuple, Any
+from dataclasses import dataclass, field
+import math
+
+from argaze import GazeFeatures
+
+import numpy
+
+@dataclass
+class VisualScanPathAnalyzer(GazeFeatures.VisualScanPathAnalyzer):
+    """Implementation of transition probability matrix algorithm as described by Christophe Lounis in its thesis "Monitor the monitoring: pilot assistance through gaze tracking and visual scanning analyses".
+    """
+
+    def __post_init__(self):
+
+        pass
+
+    def analyze(self, visual_scan_path: GazeFeatures.VisualScanPathType) -> Any:
+        """Analyze visual scan."""
+
+        assert(len(visual_scan_path) > 1)
+
+        durations = []
+        amplitudes = []
+
+        for visual_scan_step in visual_scan_path:
+
+            durations.append(visual_scan_step.duration)
+            amplitudes.append(visual_scan_step.last_saccade.amplitude)
+
+        durations = numpy.array(durations)
+        amplitudes = numpy.array(amplitudes)
+
+        duration_mean = numpy.mean(durations)
+        amplitude_mean = numpy.mean(amplitudes)
+
+        duration_std = numpy.std(durations)
+        amplitude_std = numpy.std(amplitudes)
+
+        Ks = []
+        for visual_scan_step in visual_scan_path:
+
+            Ks.append(((visual_scan_step.duration - duration_mean) / duration_std) - ((visual_scan_step.last_saccade.amplitude - amplitude_mean) / amplitude_std))
+
+        K = numpy.array(Ks).mean()
+
+        return K
+\ No newline at end of file
diff --git a/src/argaze/GazeAnalysis/__init__.py b/src/argaze/GazeAnalysis/__init__.py
index 7603693..faddbce 100644
--- a/src/argaze/GazeAnalysis/__init__.py
+++ b/src/argaze/GazeAnalysis/__init__.py
@@ -2,4 +2,4 @@
 .. include:: README.md
 """
 __docformat__ = "restructuredtext"
-__all__ = ['DispersionThresholdIdentification', 'VelocityThresholdIdentification', 'TransitionProbabilityMatrix']
-\ No newline at end of file
+__all__ = ['DispersionThresholdIdentification', 'VelocityThresholdIdentification', 'TransitionProbabilityMatrix', 'CoefficientK']
+\ No newline at end of file