feat(condition): use func directly instead variable

find_by_frequency_value() method use directly in condition instead
special variable

src/view/pages/signal_reducing.rs

@@ -132,11 +132,10 @@ pub fn signal_reducing_page(wrapper: &Box) {
 
                     let new_elem = Frequency::new(values.get().frequency);
 
-                    let exist_elem_pos = find_by_frequency_value(&model, &new_elem);
-
-                    if exist_elem_pos.is_none() {
+                    if find_by_frequency_value(&model, &new_elem).is_none() {
                         model.append(&new_elem);
                     }
+
                     update_column_view(&result_table);
                 }
             }