Update app.py

app.py

@@ -150,14 +150,18 @@ with tab1:
         st.subheader("Robot Preparation Script (Based on Ascending Order 3244 → 4882)")
         
         df_sorted_ascend = df_sorted.copy()
-        df_sorted_ascend.insert(0, 'Sample', range(1, len(df_sorted_ascend)+1))
         
+        # Only insert 'Sample' if it doesn't already exist
+        if 'Sample' not in df_sorted_ascend.columns:
+            df_sorted_ascend.insert(0, 'Sample', range(1, len(df_sorted_ascend)+1))
+        
+        # Recalculate donors and volume
         df_sorted_ascend['# donors'] = df_sorted_ascend.iloc[:, 1:].sum(axis=1)
         df_sorted_ascend['volume donors (µl)'] = 32 / df_sorted_ascend['# donors']
         
         robot_script_ascend = []
-        # Use the same source wells (length should be 32 already)
-        for i, col in enumerate(df_sorted_ascend.columns[1:33]):  # 32 binary columns
+        # Use the same 32 source wells
+        for i, col in enumerate(df_sorted_ascend.columns[1:33]):
             for row_idx, sample in df_sorted_ascend.iterrows():
                 if sample[col] == 1:
                     source = source_wells[i]
@@ -169,7 +173,6 @@ with tab1:
         st.dataframe(robot_script_ascend_df)
         st.download_button("Download Ascending Robot Script CSV", robot_script_ascend_df.to_csv(index=False), "robot_script_ascending.csv", key="download_csv_tab1_robot_ascend")
 
-
 # Tab 2: EF → Binary
 with tab2:
     st.write("Upload an Editing Frequency CSV or enter manually:")