prevent wrong index from simulator

app.py

@@ -14,6 +14,9 @@ if de_sim_file and de_exp_file:
     # Read CSV files
     sim_data = pd.read_csv(de_sim_file, header=None)
     exp_data = pd.read_csv(de_exp_file, header=None)
+    
+    center_x, center_y = sim_data.shape[1] // 2, sim_data.shape[0] // 2
+    sim_data = sim_data.iloc[center_y - 1500:center_y + 1500, center_x - 1500:center_x + 1500]
 
     # User input for line number
     line_num = st.slider("Select line number", 0, min(sim_data.shape[0], exp_data.shape[0])-1, 1499)