union of polyshapes, problem with collinearity

Hello,

I have 15 polygons (of streets) that I can merge into one using the union function.

But if I want to unite only a few of them (that are close to each other), I get:

Error using polyshape/parseCollinear (line 946)

Parameter name must be 'KeepCollinearPoints'.

Error in polyshape/parseIntersectUnionArgs (line 973)

collinear =

polyshape.parseCollinear(varargin{next_inp:end});

Error in polyshape/union (line 42)

[has_clip, collinear] = polyshape.parseIntersectUnionArgs(false,

varargin{:});

Unfortunately, I don't really understand what MatLAB wants me to do to get my unified polygon groups.

Ah, and if polygons are collinear, I'd like to keep those collinear points.

Thank you!

[Matt J]

I suggest you attach the arguments to your call to union() in a .mat file, so the community can explore the problem.

[Alexandra Kopaleyshvili]

never done this before, hope it works

Answer 1

[Matt J]

You just had a comma separated list in there by accident. The polyshapes must be given to union() as a vector.

load(websave('t','https://www.mathworks.com/matlabcentral/answers/uploaded_files/627388/streets_185.mat'));
A=union([Streetshape_185.L2{1,1}{:,1}],'KeepCollinearPoints',true)

A = 
  polyshape with properties:

      Vertices: [3604×2 double]
    NumRegions: 3
      NumHoles: 0

plot(A)

[Alexandra Kopaleyshvili]

sometimes it's so easy. thank you so much!:)