Duplicate Coordinates/Elements with Mesh2D

[jb-mackay]

Duplicate values in coordinate lists are not accounted for in Mesh2D, leading to extra copies of elements.

Minimal working example:

using ClimaCore: Domains, Meshes, Geometry
using IntervalSets

domain = Domains.RectangleDomain(
                   Geometry.XPoint(-1.)..Geometry.XPoint(1.),
                   Geometry.YPoint(-1.)..Geometry.YPoint(1.),
                   x1boundary = (:bottom, :top),
                   x2boundary = (:left, :right),
               )
m1 = Meshes.Mesh2D(domain, [-1, 0, 1], [-1, 0, 1])
m2 = Meshes.Mesh2D(domain, [-1, 0, 1, 1], [-1, 0, 1, 1])

Perhaps applying unique! to the coordinate lists is the best move, though this may require a little bit of type logic since x1c and x2c can be things like ranges. @sriharshakandala

[sriharshakandala]

@jb-mackay : Currently, the Mesh2D constructor for rectangular domains is invoked through equispaced_rectangular_mesh function.
Similarly, we can have another function that constructs the mesh using user specified x1 and x2 coordinates. Within this function, we can add checks that ensure that x1c and x2c are unique and in ascending order. We can also check to ensure the extremes of x1c and x2c are in compliance with the domain extremes.

[jb-mackay]

Thanks, @sriharshakandala, makes sense. I'm building 2D meshes with x1c and x2c to generate an overlap mesh which is not regularly spaced. The above issue is actually not a problem since I'm using a union in the constructor. I guess we can hold off on building the function you discuss until we have a use case.