normalization of methods

lib/statistics/acf/Acf.Tests.cs

@@ -416,7 +416,7 @@ public class AcfTests
         var batchResult = batchIndicator.Update(tSeries);
 
         // Mode 3: Static Calculate
-        var staticResult = Acf.Calculate(tSeries, period, lag);
+        var staticResult = Acf.Batch(tSeries, period, lag);
 
         // Mode 4: Span-based Batch
         double[] sourceArray = new double[dataLen];

lib/statistics/acf/Acf.Validation.Tests.cs

@@ -159,7 +159,7 @@ public class AcfValidationTests
             tSeries.Add(new TValue(bar.Time, bar.Close));
         }
 
-        var batch = Acf.Calculate(tSeries, period, lag);
+        var batch = Acf.Batch(tSeries, period, lag);
 
         // Compare last values
         Assert.Equal(batch[^1].Value, streaming.Last.Value, Tolerance);
@@ -182,7 +182,7 @@ public class AcfValidationTests
             tSeries.Add(new TValue(bar.Time, bar.Close));
         }
 
-        var tSeriesResult = Acf.Calculate(tSeries, period, lag);
+        var tSeriesResult = Acf.Batch(tSeries, period, lag);
 
         // Span approach
         double[] source = new double[dataLen];

lib/statistics/acf/Acf.cs

@@ -296,7 +296,7 @@ public sealed class Acf : AbstractBase
     /// <summary>
     /// Calculates ACF for a time series.
     /// </summary>
-    public static TSeries Calculate(TSeries source, int period, int lag = 1)
+    public static TSeries Batch(TSeries source, int period, int lag = 1)
     {
         var acf = new Acf(period, lag);
         return acf.Update(source);
@@ -332,6 +332,13 @@ public sealed class Acf : AbstractBase
         CalculateScalarCore(source, output, period, lag);
     }
 
+    public static (TSeries Results, Acf Indicator) Calculate(TSeries source, int period, int lag = 1)
+    {
+        var indicator = new Acf(period, lag);
+        TSeries results = indicator.Update(source);
+        return (results, indicator);
+    }
+
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     private static void CalculateScalarCore(ReadOnlySpan<double> source, Span<double> output, int period, int lag)
     {