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I have made this plot with the following code:

library(tmap)    
tm_shape(RH2) +
      tm_fill(col="AREAL") +
      tm_borders()

enter image description here

But there is a dot on the far right (an island) which I don't understand why it is there. Is there a way to limit the plot to avoid all the white spaces? like coord_fixed(xlim=c(7, 12), ylim=c(52, 58)) in ggmap?

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Have you read the help for tm_shape? It gives the following parameter:

bbox: bounding box. One of the following:

        • A bounding box (an ‘sf’ bbox object, see ‘st_bbox’, a 2
          by 2 matrix (used by the ‘sp’ package), or an ‘Extent’
          object used by the ‘raster’ package).

Its in map units rather than lat-long, so with the World data from the help you can do:

tm_shape(World, bbox=tmaptools::bb(matrix(c(0,0,2000000,2000000),2,2))) +tm_polygons()
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    @ Thanks spacedman. I will look at it tomorrow when I have my computer. But what is your take on sp vs sf objects?
    – xhr489
    Commented Jan 30, 2019 at 17:27
  • 1
    Use sf whenever possible.
    – Spacedman
    Commented Jan 30, 2019 at 22:28
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    @ Spacedman: How does one convert lon-lat units to map units?
    – xhr489
    Commented Feb 1, 2019 at 6:03
  • Its the same coordinates as the thing you have in the tm_shape function. If this is a thing in lat-long coordinates, then the map coordinates are also lat-long coordinates. But if you are working with maps in projected coordinates then you use those. see sp::spTransform or sf:st_transform for more.
    – Spacedman
    Commented Feb 1, 2019 at 7:51
  • @ Spacedman: Actually I don't think I need transforming. If I look at the "dots" geometry object and print it, the sf object prints the numbers I need for making the bbox. That is mysf_object$geometry[row_num]. But how can I get the bbox numbers for the main plot?
    – xhr489
    Commented Feb 1, 2019 at 13:53

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