opticalFlow components to complex vector field

I am trying to update legacy code that uses the no longer supported call to

opticalFlowClass = vision.OpticalFlow('OutputValue', ...
     'Horizontal and vertical components in complex form', 'Method', method);

which as the call indicates, outputs a M x N matrix in complex form. The current call, for example

    opticalFlowClass = opticalFlowHS;
    flow = estimateFlow(opticalFlowClass, video);

outputs a flow object with the components

flow.Vx
flow.Vy
flow.Magnitude
flow.Orientation

Due to dependencies elsewhere in the code and to avoid a complete rewrite, I would like to use the components from the new call to form the matrix in the complex form of the old call. However, I was unable to find any documentation how the complex form was created. My question is

What is the structure of the complex form and how was it created from the components and orientation?

Any links to old documentation that explain this would be much appreciated.

Edit: I should add that I speculate that

Flow = complex(Vx,Vy),

but I have no support for this

Answer 1

[Vishnu Sreekumar]

Field = Vx+1i.*Vy should give you the complex vector field. Then later, real(Field) and imag(Field) can be used to get the velocity components.