Question
Answer and Explanation
To remove facet grids and frames, and control coloring in R using the TMAP package, you’ll primarily utilize functions from TMAP’s API. Here's a comprehensive guide:
1. Removing Facet Grids and Frames:
TMAP, by default, does not produce facet grids in the same way that ggplot2 does. If you are seeing something that resembles facet grids or frames, this is likely coming from how the data is structured for your map or some other setting. Usually, this is a result of creating multiple maps in the same layout or specific styling applied.
To remove what might appear as "grids" or "frames," focus on controlling how the plots are laid out or remove any bounding box with `tm_layout`. If you have created multiple plots using `tmap_arrange` or the `+` operator to display them side-by-side, and these appear with separators, it means each plot is still treated as individual and you'll need to adjust them individually.
Here's how to remove frames:
tm_shape(your_shapefile) +
tm_fill("your_variable", palette = "viridis", id = "your_id") +
tm_borders(col = "transparent") +
tm_layout(frame = FALSE)
- tm_borders(col = "transparent") will remove any borders around your geometries.
- tm_layout(frame = FALSE) will remove the frame around the map itself.
2. Coloring in TMAP:
TMAP provides versatile options to color your maps. You can control color by using `tm_fill` for polygons, `tm_symbols` for points, `tm_lines` for lines, etc.
a) Using palettes:
tm_shape(your_shapefile) +
tm_fill("your_variable", palette = "viridis", id = "your_id")
- palette can be a named color palette (like "viridis", "Blues", "Reds") or a vector of colors.
b) Customizing Colors:
tm_shape(your_shapefile) +
tm_fill("your_variable", palette = c("red", "blue", "green"), id = "your_id")
- Use a vector of color names or hexadecimal color codes.
c) Categorical Colors:
tm_shape(your_shapefile) +
tm_fill("your_categorical_variable", palette = "Set3", id = "your_id")
- For categorical variables, `tmap` automatically assigns colors, and palette is very useful.
3. Example with Real Data:
library(tmap)
data(World)
tm_shape(World) +
tm_fill("life_exp", palette = "RdYlGn", id = "iso_a3") +
tm_borders(col = "transparent") +
tm_layout(frame = FALSE)
In this example, we’re using the 'World' shapefile included with TMAP, filling by 'life_exp' variable using 'RdYlGn' palette, remove borders and the frame
4. Putting it all together:
Combine `tm_borders`, `tm_layout`, and the appropriate fill function (`tm_fill`, `tm_symbols`, etc.) to control how your maps look. Always ensure you correctly pass your dataframe and variable names.
5. Additional Customizations:
You can add further customizations like legends using `tm_legend`, titles using `tm_layout(title = "Your Title")`, and more, check TMAP's documentation for all available options.
Remember, always inspect your maps and adjust the code iteratively. If you find grids, or multiple frames, consider what operation is creating them, for instance, the combination of two map layers may require a border setting or layout adjustment on each layer rather than just at the final `tmap_arrange` or similar function.