Polygon inaccuracy

[paulochf]

I found out that, in some regions, the polygons are kind of inaccurate. In my case, I was testing with some points along Spain's southern coast and eventually they got outside the polygon. When I plotted the points and the polygon, I saw a 1km-wide land strip outside the polygon, where my point was located.

I don't know if its a bug or feature, but I think it's necessary to warn this package users that it may happen.

One suggestion I can make is adding actual "timezone polygons" and use them as fallback cases.

[paulochf]

I tested the original package mattbornski/tzwhere and it returns null.

The problem isn't this package fault, but still, I guess people should know it happens.

[benjie]

Please see mattbornski/tzwhere#8 for a potential explanation.

[cstich]

I am working on a somewhat 'hacky' workaround for this.

[benjie]

@cstich I'm interested, please keep us updated :)

[cstich]

@benjie I just pushed the workaround to the development branch. It should work but I haven't done a lot of testing yet. You can see usage in the README.md. Basically you can tell the library now to look for a reasonable candidate if it doesn't find a proper timezone. If you have more than one candidate, it picks the closest. There are also potentially edge cases, where this doesn't work.

[benjie]

Neat :)

[cstich]

The code for the lookup hack is now in the master branch.

[antoniogamizbadger]

Hi, is this hack still on the package? I came here with a really similar problem:

tzwhere_instance.tzNameAt(40.689249, -74.0445)

That does not return the timezone, and I suppose it should:

That's from the google geocoding tool for developers.