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README.md

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 This is the origin Pytorch implementation of FPPformer in the following paper: 
 [Take an Irregular Route: Enhance the Decoder of Time-Series Forecasting Transformer] (Manuscript submitted to IEEE IoT).
 
+It owns two versions. The first version is the default one with channel-independent multivariate forecasting formula. The second version is the one, required by one of the reviewers, with additional cross-variable modules. Two versions are distinguished by the argument '--Cross' in main.py.
+
 ## The Entire Architecture of FPPformer
 The overview of our proposed FPPformer is illustrated in Figure 1 and its major enhancement on vanilla TSFT concentrates on addressing the preceding two problems of decoder.
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