.ln() fix

src/symbol_filter.rs

@@ -79,7 +79,7 @@ fn calc_volatility_div_price_diff(records: Value) -> Decimal {
         volatility += if volume * mid <= Decimal::ONE {
              Decimal::ZERO
         } else {
-            ((volume * mid).ln() * Decimal::ONE_HUNDRED * (record_high - record_low) / mid).ln()
+            (volume * mid).ln() * Decimal::ONE_HUNDRED * (record_high - record_low) / mid
         }
     }