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ggplot2facet-grid

How to show higher values in ggplot2 within facet_grid

I have just found the function facet_grid in ggplot2, it's awesome. The question is: I have a list with 6 countries (column HC) and destination of flights all around the world. My data look like this:

           HC Reason Destination  freq       Perc
        <chr>  <chr>       <chr> <int>      <dbl>
 1    Germany  Study     Germany     9  0.3651116
 2    Germany   Work     Germany     3  0.1488095
 3    Germany Others     Germany     3  0.4901961
 4    Hungary  Study     Germany   105 21.4285714
 5    Hungary   Work     Germany   118 17.6382661
 6    Hungary Others     Germany    24  5.0955414
 7 Luxembourg  Study     Germany   362 31.5056571

Is there a way that in each country only show the top ten destinations and using the function facet_grid? Im trying to make a scatter plot in this way:

Geograp %>% 
  gather(key=Destination, value=freq, -Reason, -Qcountry) %>%
  rename(HC = Qcountry) %>%
  group_by(HC,Reason) %>%
  mutate(Perc=freq*100/sum(freq)) %>%
  ggplot(aes(x=Perc, y=reorder(Destination,Perc))) +
  geom_point(size=3) +
  theme_bw() +
  facet_grid(HC~Reason) +
  theme(panel.grid.major.x = element_blank(),
        panel.grid.minor.x = element_blank(),
        panel.grid.major.y = element_line(colour = "grey60", linetype = "dashed"))

Which produces this graph: enter image description here I want to avoid the overplotting in the y-axis. Thanks in advance!!!

Solution

  • You could create a variable indicating the rank of each destination by country and then in the ggplot call select rows with ranking <= 10, e.g. 

    ggplot(data = mydata[rank <= 10, ], ....)

    PS: Currently you create data and plot data all in one line using pipes. I would separate the data creation and plotting step.