ImgMath: printing hierarchy of OFunction, which may have been simplified

(pruned of null ops)

Author: acardona

src/main/java/net/imglib2/algorithm/math/Compute.java

@@ -177,6 +177,16 @@ public < O extends RealType< O > > RandomAccessibleInterval< O > into(
 		return into( target, inConverter, target.randomAccess().get().createVariable(), null );
 	}
 
+	public < O extends RealType< O >, C extends RealType< C > > RandomAccessibleInterval< O > into(
+			final RandomAccessibleInterval< O > target,
+			Converter< RealType< ? >, C > inConverter,
+			final C computingType,
+			Converter< C, O > outConverter
+			)
+	{
+		return into( target, inConverter, computingType, outConverter, false );
+	}
+
 	/**
 	 * Execute the mathematical operations and store the result into the given {@code RandomAccessibleInterval}.
 	 * Takes into account whether all images involved in the computation are iterable in a compatible way.
@@ -197,6 +207,8 @@ public < O extends RealType< O > > RandomAccessibleInterval< O > into(
 	 *                 when the {@code computingType} equal the {@code Type} of the {@code target}, and a generic
 	 *                 {@code RealType} converter that uses floating-point values (with {@code RealType#setReal(double)})
 	 *                 created with {@code Util#genericRealTypeConverter()} is used.
+	 *                 
+	 * @param printHierarchy Emits to stdout the hierarchy of {@code OFunction} types.
 	 * 
 	 * @return The {@code target}.
 	 */
@@ -205,7 +217,8 @@ public < O extends RealType< O >, C extends RealType< C > > RandomAccessibleInte
 			final RandomAccessibleInterval< O > target,
 			Converter< RealType< ? >, C > inConverter,
 			final C computingType,
-			Converter< C, O > outConverter
+			Converter< C, O > outConverter,
+			final boolean printHierarchy
 			)
 	{
 		if ( null == inConverter )
@@ -222,6 +235,9 @@ public < O extends RealType< O >, C extends RealType< C > > RandomAccessibleInte
 				new HashMap< String, LetBinding< C > >(),
 				inConverter, null );
 
+		if ( printHierarchy )
+			System.out.println( Util.hierarchy( f ) );
+		
 		if ( are_same_type )
 		{
 			// Skip outputConverter: same type

src/main/java/net/imglib2/algorithm/math/abstractions/Util.java

@@ -296,7 +296,7 @@ public static final String hierarchy( final IFunction f )
 		// Iterate into the nested operations, depth-first
 		while ( ! ops.isEmpty() )
 		{
-			final IFunction  op = ops.removeFirst();
+			final IFunction op = ops.removeFirst();
 
 			String indent = indents.removeFirst();
 			String pre = "";
@@ -334,4 +334,32 @@ else if ( op instanceof Var )
 
 		return hierarchy.toString();
 	}
+	
+	public static final String hierarchy( final OFunction< ? > f )
+	{	
+		final StringBuilder hierarchy = new StringBuilder();
+		final LinkedList< String > indents = new LinkedList<>();
+		indents.add("");
+		
+		final LinkedList< OFunction< ? > > ops = new LinkedList<>();
+		ops.addLast( f );
+		
+		// Iterate into the nested operations
+		while ( ! ops.isEmpty() )
+		{
+			final OFunction< ? >  op = ops.removeFirst();
+			
+			final String indent = indents.removeFirst();
+			
+			for ( final OFunction< ? > cf : op.children() )
+			{
+				ops.addFirst( cf );
+				indents.addFirst( indent + "  " );
+			}
+			
+			hierarchy.append( indent + op.getClass().getSimpleName() + "\n");
+		}
+		
+		return hierarchy.toString();
+	}
 }