# How to find z coordinate

Hi, all
I have made a new topic for a long time.

this topic is looks so simple, but I cannot find a way to go.

Two curves have same x,y coordinates, and different z coordinates.

curve B is on the XY plane.

these two are very similar, but have different length.
(curve A length = 1198609… , curve B length = 1115900…)

and I have made the points on the curve B by segment length.
from now on, I’ll call these points “Length Points”.
obviously, Length Points are on the XY plane.

And then,
I want to find the points on the curve A that has same X,Y coordinates to “Length Points”

I am worried that my explanation might be lacking…

but you could understand what I said…

Hi, you can create planes at parameters. You can use points from curve B for parameters, or even better parameter at segment length.

When you have planes at parameters, just use geometry intersect using planes and curve A.
Hope this helps.

1 Like

create lines in Zxis direction and then intesect them with the upper curve:

3 Likes

Point.Project might also help here.

2 Likes

Thanks, Jan_Scenik !!! & Fiesta

I could not thinks of this way.
Both you solved the problem that I was worried about perfectly.

Thanks alot!!