diff --git a/algorithm/optimization/gradient.py b/algorithm/optimization/gradient.py
index b2743e3..df708df 100644
--- a/algorithm/optimization/gradient.py
+++ b/algorithm/optimization/gradient.py
@@ -121,7 +121,7 @@ class gd_1d(object):
             fig.add_trace(go.Scatter(x=xx1, y=fx))
             fig.add_traces(go.Scatter(x=None, y=None, mode="lines + markers", marker=dict(size=10), line={"color":"#de1032", "width":3, 'dash': 'dash'}))
             fig.add_traces(go.Scatter(x=None, y=None, mode="lines", line={"color":"#debc10", "width":3, 'dash': 'dash'}))
-            fig.add_traces(go.Scatter(x=None, y=None, mode="lines", line={"color":"#de3210", "width":3, 'dash': 'dash'}))
+            #fig.add_traces(go.Scatter(x=None, y=None, mode="lines", line={"color":"#de3210", "width":3, 'dash': 'dash'}))
             frames = [go.Frame(data=[go.Scatter(x=xx1, y=fx),
                                      go.Scatter(x=np.array(self.xn_list)[:k+1], y=f_xn), 
                                      go.Scatter(x=tangent_x[k], y=tangent_y[k]),