diff --git a/ddpm.py b/ddpm.py
index 10cc889..24ddad1 100644
--- a/ddpm.py
+++ b/ddpm.py
@@ -77,9 +77,21 @@ class DDPM(nn.Module):
 
                 beta = self.beta[time_seq][:, None, None, None].repeat(1, c, h, w)
 
-                z = torch.randn((n, c, h, w)).to(self.device)
+                if i!= 0:
+                    z = torch.randn((n, c, h, w)).to(self.device)
+                else:
+                    z = torch.zeros((n, c, h, w)).to(self.device)
 
                 x_t = first_term * (x_t-(second_term * predict_noise)) - z * beta
+
+                if i % (self.iteration/10) == 0:
+                    p = x_t[0].cpu()
+                    p = ( p.clamp(-1, 1) + 1 ) / 2
+                    p = p * 255
+                    p = p.permute(1, 2, 0)
+                    plt.imshow(p, vmin=0, vmax=255, cmap='gray')
+                    plt.savefig("output/iter_{}.png".format(i))
+
         x_t = ( x_t.clamp(-1, 1) + 1 ) / 2
         x_t = x_t * 255
         return x_t
\ No newline at end of file