Apologies if some of my terminology is off - I'll happily update the answer if anyone points incorrect terms out to me!
I'm using Blender 2.76
I've created a mesh; which I would like to 'close' by adding in additional faces (or surfaces; or polygons ... not sure what to call them!)
The faces parallel to the x are also open; but as those are curved; I'm just trying to full along the y axis for now.
I got the below data out of the console:
Yellow box is the face I want to add. And there are many of these running down the y axis.
I've constructed the mesh pragmatically; so I know the co-ordinates of the vertexes I want to connect with a face; so perhaps there is a simple command to add it in?