A quick alternative
ggmap
also provides a quick alternative to ggmap()
. Like qplot()
in ggplot2
, qmplot()
is less flexible than a full specification, but often involves significantly less typing. qmplot()
replaces both steps -- downloading the map and displaying the map -- and its syntax is a blend between qplot()
, get_map()
, and ggmap()
.
Let's take a look at the qmplot()
version of the faceted plot from the previous exercise:
qmplot(lon, lat, data = sales,
geom = "point", color = class) +
facet_wrap(~ class)
Notice we didn't specify a map, since qmplot()
will grab one on its own. Otherwise the qmplot()
call looks a lot like the corresponding qplot()
call: use points to display the sales
data, mapping lon
to the x-axis, lat
to the y-axis, and class
to color. qmplot()
also sets the default dataset and mapping (without the need for base_layer
) so you can add facets without any extra work.
This exercise is part of the course
Visualizing Geospatial Data in R
Exercise instructions
Using the example as a guide, use qmplot()
to create a plot of the house sales where color is mapped to bedrooms
, faceted by month
.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Plot house sales using qmplot()