How to get 3D position in Unity?

Developer Resources Getting Started
1

how to use the following portion?

how to get 3D position using the following API ?

mapper.MapDepthPointToWorldSpace(new Vector3D(x, y, depthValue));

void PrintDepth(Astra.DepthFrame depthFrame,
Astra.CoordinateMapper mapper)
{
if (depthFrame != null)
{
int width = depthFrame.Width;
int height = depthFrame.Height;
long frameIndex = depthFrame.FrameIndex;

        //determine if buffer needs to be reallocated
        if (width != _lastWidth || height != _lastHeight)
        {
            _buffer = new short[width * height];
            _lastWidth = width;
            _lastHeight = height;
        }
        depthFrame.CopyData(ref _buffer);

        int index = (int)((width * (height / 2.0f)) + (width / 2.0f));
        short middleDepth = _buffer[index];

        Vector3D worldPoint = mapper.MapDepthPointToWorldSpace(new Vector3D(width / 2.0f, height / 2.0f, middleDepth));
        Vector3D depthPoint = mapper.MapWorldPointToDepthSpace(worldPoint);

        Debug.Log("depth frameIndex: " + frameIndex
                  + " width: " + width
                  + " height: " + height
                  + " middleDepth: " + middleDepth
                  + " wX: " + worldPoint.X
                  + " wY: " + worldPoint.Y
                  + " wZ: " + worldPoint.Z
                  + " dX: " + depthPoint.X
                  + " dY: " + depthPoint.Y
                  + " dZ: " + depthPoint.Z + " frameCount: " + _frameCount);
    }
}

There is no template and no example for the implementation of this part.

Any help or a small script would be highly appreciable.

Prasanna.