Fixing a station's height only, or x,y only

[Les Williams]

Hi Tarquin
Surely the x, y and z are actually representative of the same point, 
i.e. an "imaginary point" centred inside the trig point directly below 
the centre of the circle and at an altitude of z. This point will have 
the same x and y coordinates as the circle on the top, and the same 
altitude as the bench mark on the side.
As such, why6 don't you just fix that imaginary point.

Les

On 14/08/2021 20:30, Tarquin Wilton-Jones wrote:
> Hi,
>
> I have a survey that starts at a trigpoint. The trigpoint has a height
> specified for the benchmark bracket on its side, and x,y coordinates for
> the circle on its top. The survey has stations on both the benchmark and
> the centre of the top.
>
> I need to be able to specify the x,y for the top, and the z for the
> bracket on the side.
>
> Can survex allow me to do this, or do I need to do all the maths myself
> to work out the height of the top so I can fix all three coordinate
> dimensions for a single point?
>
> What I want is this:
> *fix 2 - - 123.4
> *fix 4 1234.5 6789.0 -
>
> >From what I can see in the docs, none of these parameters are optional,
> so how can you deal with situation in survex?
>
> Cheers,
>
> Tarquin
>