Efficient Sleep Stage Identification Using Piecewise Linear EEG Signal Reduction: A Novel Algorithm for Sleep Disorder Diagnosis

. 2024 Aug 14;24(16):5265. doi: 10.3390/s24165265

Algorithm 2 Expanded Computation of Euclidean Distance Matrix

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Input: $X \in R^{d \times n}$
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$G \leftarrow ZeroMatrix (n, n)$ ▹ Initialize the Gram matrix
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for $i = 1$ to n do
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for $j = 1$ ton do
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$G [i, j] \leftarrow \sum_{k = 1}^{d} X [k, i] \times X [k, j]$ ▹ Compute the Gram matrix
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end for
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end for
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$D \leftarrow ZeroMatrix (n, n)$ ▹ Initialize the distance matrix
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for $i = 1$ to n do
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for $j = 1$ ton do
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$D [i, j] \leftarrow G [i, i] + G [j, j] - 2 \times G [i, j]$ ▹ Compute the distance matrix
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end for
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end for
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Output: D