add option for random fourier features, given misinterpretation of Katherine's code, thanks to @tmabraham for addressing this in https://github.com/lucidrains/denoising-diffusion-pytorch/issues/112

denoising_diffusion_pytorch/continuous_time_gaussian_diffusion.py

@@ -126,7 +126,7 @@ class ContinuousTimeGaussianDiffusion(nn.Module):
         p2_loss_weight_k = 1
     ):
         super().__init__()
-        assert model.learned_sinusoidal_cond
+        assert model.random_or_learned_sinusoidal_cond
         assert not model.self_condition, 'not supported yet'
 
         self.model = model