Model param.grad is None, how to debug?

[anum_abdul_salam]

@ptrblck please look into this issue

Param.grad is always None

def calculate_fisher_matrix_3(task_model, train_loader, criterion, feature_extractor, num_samples=1000): task_model.train() optimizer = optim.Adam(model.parameters(), lr=0.001) fisher_matrix = [torch.zeros_like(param.data) for param in task_model.parameters()] total_samples = 0 for i, data in enumerate(train_loader, 0): inputs = data["pixel_values"].requires_grad_(True) labels = data["labels"].float().requires_grad_(True) sizei = data["pixel_values"].shape[2], data["pixel_value…