diff --git a/color-palette/README.md b/color-palette/README.md
index e91df21..a1c48aa 100644
--- a/color-palette/README.md
+++ b/color-palette/README.md
@@ -1,18 +1,33 @@
 ```python
+''
 # https://iquilezles.org/articles/palettes/
 import numpy as np
 
-W, H = 800, 20
+W, H = 800, 40
 imgs = []
-for _ in range(50):
+for _ in range(20):
     a, b, c, d = np.random.rand(4, 3)
-    # b = a * b
     # c = np.ones(3)
-    palette = lambda t: np.clip(a + b * np.cos(np.pi * (c * t + d)), 0, 1)
+    palette = lambda t: np.clip(a + b * np.cos(2 * np.pi * (c * t + d)), 0, 1)
     line = [palette(t) for t in np.linspace(0, 1, W)]
     img = np.stack([line] * H)
     img = (img * 255).astype(np.uint8)
     imgs.append(img)
 img = np.vstack(imgs)
 __import__('PIL.Image').Image.fromarray(img)
+''
+import numpy as np
+a, b, c, d = np.array([
+    [.5, .5, .5],
+    [.5, .5, .5],
+    [1., 1., 1.],
+    [0., .33, .67]])
+
+W, H = 800, 20
+palette = lambda t: np.clip(a + b * np.cos(2 * np.pi * (c * t + d)), 0, 1)
+line = [palette(t) for t in np.linspace(0, 1, W)]
+img = (np.stack([line] * H) * 255).astype(np.uint8)
+__import__('PIL.Image').Image.fromarray(img)
+''
+
 ```
\ No newline at end of file