Vector memory exhausted

[MauKruisheer]

Thank you for this great tutorial! I would really like to reproduce this code for the country Kenya, but I have run into this error (which refers to line 161, the ggplot2 section). I tried lower the n class from 5 to 3, to safe memory (?), but this did not work. Any idea how to overcome this issue? Much appreciated!

Error in `geom_raster()` at Projects/ForestHeight/ForestHeight_Kenya.r:161:0:
! Problem while converting geom to grob.
ℹ Error occurred in the 1st layer.
Caused by error:
! vector memory exhausted (limit reached?)
Run `rlang::last_trace()` to see where the error occurred.
Warning messages:
1: In classInt::classIntervals(forest_height_kenya_df$height, n = 3,  :
  N is large, and some styles will run very slowly; sampling imposed
2: Raster pixels are placed at uneven horizontal intervals and will be shifted
ℹ Consider using `geom_tile()` instead. 
3: Raster pixels are placed at uneven horizontal intervals and will be shifted
ℹ Consider using `geom_tile()` instead. 

[MauKruisheer]

Hey, I am still wondering if anyone has any ideas on how to overcome this. Very welcome, and much appreciated. Thanks, Maurits