Hi everybody,
I have created a grid and now I want to build walls on the surrounding lines. I only Need the first and the last item of the list.
I know that I can achieve this by using an Expression. I simply dont know what I have to type in. Of Course I could just say: LinesGridX[2] and then it would get me this particular item. The Problem is, that i always have to rewrite the Code, when I Change the number of Grid Lines.
Here is an Image of my model so far:
Thank you for your help
Heiko
.... so in your case LinesGridX[NumberGridLinesX]
I made an Expression with the following script now:
{LinesGridX.Last(1),LinesGridX.First(1),LinesGridY.Last(1),LinesGridY.First(1)}
These are all the surrounding lines. My Problem is, that they are now values of an Expression and I dont know how to make lines out of them. Right now the Output of my Expression-node doesnt fit.
Do you know what I mean?
I think if you somehow sketch the goal you're heading for it would be easier to give you a hint.
Do you want to...
... get a polygon on your outer lines?
... some points with offset to the outer lines?
...
I want to build walls on the outer lines. I think something like a Polyline would work, that connects all outer lines.
With my expression I already selected the lines but I need to know how I can use the output of the expression o make it a polyline.
If I put a node "polyline" behind the expression, how do I heave to define the inputs for it? I first thought it would work with the input definition "Polyline.byElement but If I choose this definition, the node doesnt work.
Here is probably something you might want to achieve - but there are problems with the graphics.
Ingo
For lists, there are a few methods which are available through auto-completion. In this case, List.First() and List.Last() are methods to retrieve the first and last items of a list, respectively. They can also take an integer number as an argument which then indicates how many "first" or "last" members of the list are returned by the expression.