first commit

layers/EMA.py

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+import torch
+from torch import nn
+
+class EMA(nn.Module):
+    """
+    Exponential Moving Average (EMA) block to highlight the trend of time series
+    """
+    def __init__(self, alpha):
+        super(EMA, self).__init__()
+        self.alpha = alpha
+
+    def forward(self, x):
+        # x: [Batch, Input, Channel]
+        _, t, _ = x.shape
+        powers = torch.flip(torch.arange(t, dtype=torch.double), dims=(0,))
+        weights = torch.pow((1 - self.alpha), powers).to(x.device)
+        divisor = weights.clone()
+        weights[1:] = weights[1:] * self.alpha
+        weights = weights.reshape(1, t, 1)
+        divisor = divisor.reshape(1, t, 1)
+        x = torch.cumsum(x * weights, dim=1)
+        x = torch.div(x, divisor)
+        return x.to(torch.float32)