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Model: google/gemini-3.1-pro-preview
Total steps: 6
Messages: 13
UserStep 0

Task: ts-short-term-forecast

Short-Term Time Series Forecasting: Custom Model Design

Objective

Design and implement a custom deep learning model for univariate short-term time series forecasting on the M4 dataset. Your code goes in the Model class in models/Custom.py. Three reference implementations (DLinear, TimesNet, PatchTST) are provided as read-only.

Evaluation

Trained and evaluated on three M4 seasonal patterns:

  • Monthly (pred_len=18, seq_len=104)
  • Quarterly (pred_len=8, seq_len=52)
  • Yearly (pred_len=6, seq_len=42)

All use enc_in=1, features=M, loss=SMAPE. Metric: SMAPE (lower is better).

Time-Series-Library/models/Custom.py [EDITABLE — entire file only]

     1: import torch
     2: import torch.nn as nn
     3: 
     4: 
     5: class Model(nn.Module):
     6:     """
     7:     Custom model for short-term time series forecasting (M4 dataset).
     8: 
     9:     Forward signature: forward(x_enc, x_mark_enc, x_dec, x_mark_dec, mask=None)
    10:     - x_enc: [batch, seq_len, enc_in] — input time series (enc_in=1 for M4)
    11:     - x_mark_enc: [batch, seq_len, time_features] — time feature encoding
    12:     - x_dec: [batch, label_len+pred_len, dec_in] — decoder input
    13:     - x_mark_dec: [batch, label_len+pred_len, time_features] — decoder time features
    14: 
    15:     Must return: [batch, pred_len, c_out] for forecasting
    16:     """
    17: 
    18:     def __init__(self, configs):
    19:         super(Model, self).__init__()
    20:         self.task_name = configs.task_name
    21:         self.seq_len = configs.seq_len
    22:         self.pred_len = configs.pred_len
    23:         self.enc_in = configs.enc_in
    24:         self.c_out = configs.c_out
    25:         # TODO: Define your model architecture here
    26: 
    27:     def forecast(self, x_enc, x_mark_enc, x_dec, x_mark_dec):
    28:         """
    29:         Forecasting: given input sequence, predict future values.
    30:         Input: x_enc [batch, seq_len, 1]
    31:         Output: [batch, pred_len, 1]
    32:         """
    33:         # TODO: Implement your forecasting logic
    34:         batch_size = x_enc.shape[0]
    35:         return torch.zeros(batch_size, self.pred_len, self.c_out).to(x_enc.device)
    36: 
    37:     def forward(self, x_enc, x_mark_enc, x_dec, x_mark_dec, mask=None):
    38:         if self.task_name == 'long_term_forecast' or self.task_name == 'short_term_forecast':
    39:             dec_out = self.forecast(x_enc, x_mark_enc, x_dec, x_mark_dec)
    40:             return dec_out[:, -self.pred_len:, :]
    41:         return None

Time-Series-Library/models/DLinear.py [READ-ONLY — do not edit]

     1: import torch
     2: import torch.nn as nn
     3: import torch.nn.functional as F
     4: from layers.Autoformer_EncDec import series_decomp
     5: 
     6: 
     7: class Model(nn.Module):
     8:     """
     9:     Paper link: https://a
AssistantStep 1edit
Tool Input
1{
2  "end_line": 41,
3  "op": "replace",
4  "start_line": 1,
5  "filename": "Time-Series-Library/models/Custom.py",
6  "content": "import torch\nimport torch.nn as nn\nimport torch.nn.functional as F\n\nclass SpectralMoEBlock(nn.Module):\n    def __init__(self, seq_len, pred_len, num_experts=3):\n        super(SpectralMoEBlock, self).__init__()\n        self.seq_len = seq_len\n        self.pred_len = pred_len\n        self.num_experts = num_experts\n        freq_len = seq_len // 2 + 1\n        \n        self.gate = nn.Sequential(\n            nn.Linear(freq_len, 64),\n            nn.GELU(),\n            nn.Linear(64, freq_len * num_experts)\n        )\n        \n        self.forecast_experts = nn.ModuleList([\n            nn.Linear(seq_len, pred_len) for _ in range(num_experts)\n        ])\n        \n        self.backcast_experts = nn.ModuleList([\n            nn.Linear(seq_len, seq_len) for _ in range(num_experts)\n        ])\n\n    def forward(self, x):\n        # x: [B, D, L]\n        batch_size, D, L = x.shape\n        freq_len = L // 2 + 1\n        \n        # FFT\n        xfft = torch.fft.rfft(x, dim=-1) # [B, D, freq_len]\n        amp = torch.abs(xfft) # [B, D, freq_len]\n        \n        # Gating\n        logits = self.gate(amp) # [B, D, freq_len * num_experts]\n        logits = logits.view(batch_size, D, freq_len, self.num_experts)\n        gates = torch.softmax(logits, dim=-1) # [B, D, freq_len, num_experts]\n        \n        # Expert specific signals\n        y_forecast = 0\n        x_backcast = 0\n        \n        for k in range(self.num_experts):\n            # Masking in freq domain\n            mask_k = gates[..., k] # [B, D, freq_len]\n            xfft_k = xfft * mask_k\n            \n            # Inverse FFT\n            x_k = torch.fft.irfft(xfft_k, n=self.seq_len, dim=-1) # [B, D, L]\n            \n            # Linear projection\n            y_forecast = y_forecast + self.forecast_experts[k](x_k)\n            x_backcast = x_backcast + self.backcast_experts[k](x_k)\n            \n        return x_backcast, y_forecast\n\nclass Model(nn.Module):\n    \"\"\"\n    Custom model for short-term time series forecasting (M4 dataset).\n    Incorporates Spectral Mixture of Experts (Spectral-MoE) on continuous residual blocks.\n    Algorithm:\n    1. Input is Instance Normalized.\n    2. Deep Residual Blocks sequentially operate on the series.\n    3. Within each block, a dynamic frequency-domain router (MoE) isolates\n       sub-spaces (e.g. dynamic low/high pass filtering) learned from the signal amplitude.\n    4. Time-domain linear experts specialize in predicting future (forecast) \n       and reconstructing the input (backcast).\n    \"\"\"\n\n    def __init__(self, configs):\n        super(Model, self).__init__()\n        self.task_name = configs.task_name\n        self.seq_len = configs.seq_len\n        self.pred_len = configs.pred_len\n        self.enc_in = configs.enc_in\n        self.c_out = configs.c_out\n        \n        self.num_blocks = 3  # Deep residual stages\n        num_experts = 3      # Specialists per stage\n        \n        self.blocks = nn.ModuleList([\n            SpectralMoEBlock(self.seq_len, self.pred_len, num_experts=num_experts)\n            for _ in range(self.num_blocks)\n        ])\n        \n        if self.c_out != self.enc_in:\n            self.projection = nn.Linear(self.enc_in, self.c_out)\n        else:\n            self.projection = None\n\n    def forecast(self, x_enc, x_mark_enc, x_dec, x_mark_dec):\n        \"\"\"\n        Forecasting logic.\n        Input: x_enc [batch, seq_len, enc_in]\n        Output: [batch, pred_len, c_out]\n        \"\"\"\n        # RevIN-like Instance Normalization\n        means = x_enc.mean(dim=1, keepdim=True).detach()\n        x_enc_norm = x_enc - means\n        stdev = torch.sqrt(torch.var(x_enc_norm, dim=1, keepdim=True, unbiased=False) + 1e-5)\n        x_enc_norm = x_enc_norm / stdev\n        \n        # Reshape to [B, D, L]\n        x = x_enc_norm.transpose(1, 2)\n        \n        y_pred = torch.zeros(x.shape[0], x.shape[1], self.pred_len, device=x.device)\n        \n        for block in self.blocks:\n            x_backcast, block_forecast = block(x)\n            x = x - x_backcast\n            y_pred = y_pred + block_forecast\n            \n        # Reshape back to [B, L, D]\n        y_pred = y_pred.transpose(1, 2)\n        \n        # De-Normalization\n        y_pred = y_pred * (stdev[:, 0, :].unsqueeze(1).repeat(1, self.pred_len, 1))\n        y_pred = y_pred + (means[:, 0, :].unsqueeze(1).repeat(1, self.pred_len, 1))\n        \n        if self.projection is not None:\n            y_pred = self.projection(y_pred)\n            \n        return y_pred\n\n    def forward(self, x_enc, x_mark_enc, x_dec, x_mark_dec, mask=None):\n        if self.task_name == 'long_term_forecast' or self.task_name == 'short_term_forecast':\n            dec_out = self.forecast(x_enc, x_mark_enc, x_dec, x_mark_dec)\n            return dec_out[:, -self.pred_len:, :]\n        return None\n"
7}
Tool ResultStep 1
OK: Replaced lines 1..41 with 131 line(s) in Time-Series-Library/models/Custom.py. Editable range: entire file.

[Current file: Time-Series-Library/models/Custom.py | editable: 1–131 | total: 131 lines]
     1  import torch
     2  import torch.nn as nn
     3  import torch.nn.functional as F
     4  
     5  class SpectralMoEBlock(nn.Module):
     6      def __init__(self, seq_len, pred_len, num_experts=3):
     7          super(SpectralMoEBlock, self).__init__()
     8          self.seq_len = seq_len
     9          self.pred_len = pred_len
    10          self.num_experts = num_experts
    11          freq_len = seq_len // 2 + 1
    12          
    13          self.gate = nn.Sequential(
    14              nn.Linear(freq_len, 64),
    15              nn.GELU(),
    16              nn.Linear(64, freq_len * num_experts)
    17          )
    18          
    19          self.forecast_experts = nn.ModuleList([
    20              nn.Linear(seq_len, pred_len) for _ in range(num_experts
AssistantStep 2test
Tool ResultStep 2
[Test #1] (2 tests remaining; call submit(n=1) to submit this result)

### m4_monthly (scripts/m4_monthly.sh)
Training metrics (last epochs):
TRAIN_METRICS epoch=6 train_loss=7.5575331 vali_loss=12.6898486
TRAIN_METRICS epoch=7 train_loss=7.5059884 vali_loss=12.6873497
TRAIN_METRICS epoch=8 train_loss=7.5161928 vali_loss=12.6778644
TRAIN_METRICS epoch=9 train_loss=7.4975956 vali_loss=12.6618254
TRAIN_METRICS epoch=10 train_loss=7.4870430 vali_loss=12.6664189
Test results (m4_monthly):
  SMAPE: 12.6618, MAPE: 12.6618, MAPE: 0.1482

### m4_quarterly (scripts/m4_quarterly.sh)
Training metrics (last epochs):
TRAIN_METRICS epoch=6 train_loss=7.0679929 vali_loss=10.1052971
TRAIN_METRICS epoch=7 train_loss=7.0874488 vali_loss=10.0838983
TRAIN_METRICS epoch=8 train_loss=7.0162592 vali_loss=10.0911399
TRAIN_METRICS epoch=9 train_loss=6.9993838 vali_loss=10.0870180
TRAIN_METRICS epoch=10 train_loss=6.9955672 vali_loss=10.0901283
Test results (m4_quarterly):
  SMAPE: 10.0839, MAPE: 10.0839, MAPE:
AssistantStep 3edit
Tool Input
1{
2  "end_line": 81,
3  "start_line": 80,
4  "content": "        self.num_blocks = 2  # Deep residual stages\n        num_experts = 4      # Specialists per stage\n",
5  "filename": "Time-Series-Library/models/Custom.py",
6  "op": "replace"
7}
Tool ResultStep 3
OK: Replaced lines 80..81 with 2 line(s) in Time-Series-Library/models/Custom.py. Editable range: entire file.

[Current file: Time-Series-Library/models/Custom.py | editable: 1–131 | total: 131 lines]
     1  import torch
     2  import torch.nn as nn
     3  import torch.nn.functional as F
     4  
     5  class SpectralMoEBlock(nn.Module):
     6      def __init__(self, seq_len, pred_len, num_experts=3):
     7          super(SpectralMoEBlock, self).__init__()
     8          self.seq_len = seq_len
     9          self.pred_len = pred_len
    10          self.num_experts = num_experts
    11          freq_len = seq_len // 2 + 1
    12          
    13          self.gate = nn.Sequential(
    14              nn.Linear(freq_len, 64),
    15              nn.GELU(),
    16              nn.Linear(64, freq_len * num_experts)
    17          )
    18          
    19          self.forecast_experts = nn.ModuleList([
    20              nn.Linear(seq_len, pred_len) for _ in range(num_experts)
AssistantStep 4test
Tool ResultStep 4
[Test #2] (1 test remaining; call submit(n=2) to submit this result)

### m4_monthly (scripts/m4_monthly.sh)
Training metrics (last epochs):
TRAIN_METRICS epoch=6 train_loss=7.4763590 vali_loss=12.6904281
TRAIN_METRICS epoch=7 train_loss=7.4498906 vali_loss=12.6508191
TRAIN_METRICS epoch=8 train_loss=7.5106367 vali_loss=12.6536975
TRAIN_METRICS epoch=9 train_loss=7.4840158 vali_loss=12.6542170
TRAIN_METRICS epoch=10 train_loss=7.4927647 vali_loss=12.6512725
Test results (m4_monthly):
  SMAPE: 12.6508, MAPE: 12.6508, MAPE: 0.1473

### m4_quarterly (scripts/m4_quarterly.sh)
Training metrics (last epochs):
TRAIN_METRICS epoch=6 train_loss=6.9588442 vali_loss=10.1507261
TRAIN_METRICS epoch=7 train_loss=7.0156102 vali_loss=10.1399915
TRAIN_METRICS epoch=8 train_loss=7.0486403 vali_loss=10.1360787
TRAIN_METRICS epoch=9 train_loss=7.0104080 vali_loss=10.1394913
TRAIN_METRICS epoch=10 train_loss=7.0089109 vali_loss=10.1346209
Test results (m4_quarterly):
  SMAPE: 10.1346, MAPE: 10.1346, MAPE: 
AssistantStep 5edit
Tool Input
1{
2  "end_line": 131,
3  "start_line": 1,
4  "filename": "Time-Series-Library/models/Custom.py",
5  "op": "replace",
6  "content": "import torch\nimport torch.nn as nn\nimport torch.nn.functional as F\nfrom layers.Autoformer_EncDec import series_decomp\n\nclass SpectralMoEBlock(nn.Module):\n    def __init__(self, seq_len, pred_len, num_experts=3):\n        super(SpectralMoEBlock, self).__init__()\n        self.seq_len = seq_len\n        self.pred_len = pred_len\n        self.num_experts = num_experts\n        freq_len = seq_len // 2 + 1\n        \n        self.gate = nn.Sequential(\n            nn.Linear(freq_len, 64),\n            nn.GELU(),\n            nn.Dropout(0.1),\n            nn.Linear(64, freq_len * num_experts)\n        )\n        \n        self.forecast_experts = nn.ModuleList([\n            nn.Linear(seq_len, pred_len) for _ in range(num_experts)\n        ])\n        \n        self.backcast_experts = nn.ModuleList([\n            nn.Linear(seq_len, seq_len) for _ in range(num_experts)\n        ])\n\n    def forward(self, x):\n        batch_size, D, L = x.shape\n        freq_len = L // 2 + 1\n        \n        xfft = torch.fft.rfft(x, dim=-1) \n        amp = torch.abs(xfft) \n        \n        logits = self.gate(amp) \n        logits = logits.view(batch_size, D, freq_len, self.num_experts)\n        gates = torch.softmax(logits, dim=-1) \n        \n        y_forecast = 0\n        x_backcast = 0\n        \n        for k in range(self.num_experts):\n            mask_k = gates[..., k] \n            xfft_k = xfft * mask_k\n            \n            x_k = torch.fft.irfft(xfft_k, n=self.seq_len, dim=-1) \n            \n            y_forecast = y_forecast + self.forecast_experts[k](x_k)\n            x_backcast = x_backcast + self.backcast_experts[k](x_k)\n            \n        return x_backcast, y_forecast\n\nclass Model(nn.Module):\n    def __init__(self, configs):\n        super(Model, self).__init__()\n        self.task_name = configs.task_name\n        self.seq_len = configs.seq_len\n        self.pred_len = configs.pred_len\n        self.enc_in = configs.enc_in\n        self.c_out = configs.c_out\n        \n        self.decomp = series_decomp(25)\n        self.linear_trend = nn.Linear(self.seq_len, self.pred_len)\n        \n        self.num_blocks = 3  \n        num_experts = 3      \n        \n        self.blocks = nn.ModuleList([\n            SpectralMoEBlock(self.seq_len, self.pred_len, num_experts=num_experts)\n            for _ in range(self.num_blocks)\n        ])\n        \n        if self.c_out != self.enc_in:\n            self.projection = nn.Linear(self.enc_in, self.c_out)\n        else:\n            self.projection = None\n\n    def forecast(self, x_enc, x_mark_enc, x_dec, x_mark_dec):\n        # RevIN-like Instance Normalization\n        means = x_enc.mean(dim=1, keepdim=True).detach()\n        x_enc_norm = x_enc - means\n        stdev = torch.sqrt(torch.var(x_enc_norm, dim=1, keepdim=True, unbiased=False) + 1e-5)\n        x_enc_norm = x_enc_norm / stdev\n        \n        # Decomposition\n        res, trend = self.decomp(x_enc_norm) # [B, L, D]\n        \n        y_trend = self.linear_trend(trend.transpose(1, 2)).transpose(1, 2)\n        \n        # Reshape to [B, D, L] for Spectral blocks\n        x = res.transpose(1, 2)\n        \n        y_sea = torch.zeros(x.shape[0], x.shape[1], self.pred_len, device=x.device)\n        \n        for block in self.blocks:\n            x_backcast, block_forecast = block(x)\n            x = x - x_backcast\n            y_sea = y_sea + block_forecast\n            \n        y_sea = y_sea.transpose(1, 2) # [B, pred_len, D]\n        \n        y_pred = y_trend + y_sea\n        \n        # De-Normalization\n        y_pred = y_pred * (stdev[:, 0, :].unsqueeze(1).repeat(1, self.pred_len, 1))\n        y_pred = y_pred + (means[:, 0, :].unsqueeze(1).repeat(1, self.pred_len, 1))\n        \n        if self.projection is not None:\n            y_pred = self.projection(y_pred)\n            \n        return y_pred\n\n    def forward(self, x_enc, x_mark_enc, x_dec, x_mark_dec, mask=None):\n        if self.task_name == 'long_term_forecast' or self.task_name == 'short_term_forecast':\n            dec_out = self.forecast(x_enc, x_mark_enc, x_dec, x_mark_dec)\n            return dec_out[:, -self.pred_len:, :]\n        return None"
7}
Tool ResultStep 5
OK: Replaced lines 1..131 with 118 line(s) in Time-Series-Library/models/Custom.py. Editable range: entire file.

[Current file: Time-Series-Library/models/Custom.py | editable: 1–118 | total: 118 lines]
     1  import torch
     2  import torch.nn as nn
     3  import torch.nn.functional as F
     4  from layers.Autoformer_EncDec import series_decomp
     5  
     6  class SpectralMoEBlock(nn.Module):
     7      def __init__(self, seq_len, pred_len, num_experts=3):
     8          super(SpectralMoEBlock, self).__init__()
     9          self.seq_len = seq_len
    10          self.pred_len = pred_len
    11          self.num_experts = num_experts
    12          freq_len = seq_len // 2 + 1
    13          
    14          self.gate = nn.Sequential(
    15              nn.Linear(freq_len, 64),
    16              nn.GELU(),
    17              nn.Dropout(0.1),
    18              nn.Linear(64, freq_len * num_experts)
    19          )
    20          
    21          self.forecast_expe
AssistantStep 6test
Tool ResultStep 6
[Test #3] (0 tests remaining)

### m4_monthly (scripts/m4_monthly.sh)
Training metrics (last epochs):
TRAIN_METRICS epoch=6 train_loss=7.5242806 vali_loss=12.5888643
TRAIN_METRICS epoch=7 train_loss=7.4772877 vali_loss=12.5883550
TRAIN_METRICS epoch=8 train_loss=7.4552466 vali_loss=12.5889552
TRAIN_METRICS epoch=9 train_loss=7.5464168 vali_loss=12.5904477
TRAIN_METRICS epoch=10 train_loss=7.4413244 vali_loss=12.5880354
Test results (m4_monthly):
  SMAPE: 12.5880, MAPE: 12.5880, MAPE: 0.1470

### m4_quarterly (scripts/m4_quarterly.sh)
Training metrics (last epochs):
TRAIN_METRICS epoch=6 train_loss=7.0015219 vali_loss=10.1300181
TRAIN_METRICS epoch=7 train_loss=6.9824530 vali_loss=10.1373438
TRAIN_METRICS epoch=8 train_loss=6.9556818 vali_loss=10.1225164
TRAIN_METRICS epoch=9 train_loss=7.0714006 vali_loss=10.1192015
TRAIN_METRICS epoch=10 train_loss=7.0115321 vali_loss=10.1189755
Test results (m4_quarterly):
  SMAPE: 10.1190, MAPE: 10.1190, MAPE: 0.1157

### m4_yearly (scripts/m4_yearl