raster::plot() plotting raster too small- is there an alternative on ggplot?

Question

I am trying to plot this raster on R. The object is quite big, but when plotting it using the raster::plot() function, I obtain a very tiny image, as attached.

The code I use to produce it is the following:

r <- raster::raster("MOD13Q1_2000-02-18.250m_16_days_NDVI.tif")
r <- setMinMax(r)
raster::plot(r)

I tried to set xlim limits, with no success. I then tried to move to ggplot2, as an alternative (following here), but I obtain the following

ggplot(r) + geom_tile(aes(fill=value))
Error: ggplot2 doesn't know how to deal with data of class RasterLayer

I found around that, to plot raster objects with ggplot(), I should first convert it into a data.frame. However, as my object is quite big (about 55million obs.), that would be very inefficient. I am then stuck on what to do. Any thoughts?

Answer 1

The base plot method works fine for me:

so I suspect something has gone amiss with your graphics device. If using rstudio, I think there's a little button to reset the graphics window, otherwise try dev.off() to switch the graphics window off, and the next plot will create a new one.

This behaviour generally happens when a previous graphics operation has left the graphics device in a non-default state, such as having divided it up to put a legend in a section of window. A reset as described above usually helps.

There's no need to look to ggplot - the raster package plot methods are very well optimised for big rasters and will sample down large rasters for speed.

Answer 2

In addition to @Spacedman answer... Sometimes, some packages change plot parameters.

You need to set back default parameters and plot again:

r <- raster::raster("MOD13Q1_2000-02-18.250m_16_days_NDVI.tif")

par(mar = c(5.1, 4.1, 4.1, 2.1), mgp = c(3, 1, 0), mfrow = c(1,1), las = 0)

plot(r)

You can also include this into plot function to override an unexpect behaivour:

r <- raster::raster("MOD13Q1_2000-02-18.250m_16_days_NDVI.tif")

plot(r,mar = c(5.1, 4.1, 4.1, 2.1), mgp = c(3, 1, 0), mfrow = c(1,1), las = 0)