code: static public void intensityE(GrayF32 derivX , GrayF32 derivY , GrayF32 intensity )
  	{
  		InputSanityCheck.checkSameShape(derivX,derivY);
  		intensity.reshape(derivX.width,derivX.height);
  
  		if(BoofConcurrency.USE_CONCURRENT ) {
  			ImplGradientToEdgeFeatures_MT.intensityE(derivX,derivY,intensity);
  		} else {
  			ImplGradientToEdgeFeatures.intensityE(derivX,derivY,intensity);
  		}
  	}
docs: Computes the edge intensity using a Euclidean norm.
  
  @param derivX Derivative along x-axis. Not modified.
  @param derivY Derivative along y-axis. Not modified.
  @param intensity Edge intensity.