Menu
I want to plot a subset of my dataframe. I am working with dplyr and ggplot2. My code only works with version 1, not version 2 via piping. What's the difference?
Version 1 (plotting is working):
data <- dataset %>% filter(type=="type1")
ggplot(data, aes(x=year, y=variable)) + geom_line()
Version 2 with piping (plotting is not working):
data %>% filter(type=="type1") %>% ggplot(data, aes(x=year, y=variable)) + geom_line()
Error:
Error in ggplot.data.frame(., data, aes(x = year, :
Mapping should be created with aes or aes_string
Thanks for your help!
1000
%>% is a pipe operator reexported from the magrittr package. Start by reading the vignette. Adding things to a ggplot changes the object that gets created. The print method of ggplot draws an appropriate plot depending upon the contents of the variable.
The %>% operator can also be used to pipe the dplyr output into ggplot. This creates a unified exploratory data analysis (EDA) pipeline that is easily customizable. This method is faster than doing the aggregations internally in ggplot and has the added benefit of avoiding unnecessary intermediate variables.
ggplot only works with data frames, so we need to convert this matrix into data frame form, with one measurement in each row. We can convert to this “long” form with the melt function in the library reshape2 . Notice how ggplot is able to use either numerical or categorical (factor) data as x and y coordinates.
ggplot2 [library(ggplot2)] ) is a plotting library for R developed by Hadley Wickham, based on Leland Wilkinson's landmark book The Grammar of Graphics ["gg" stands for Grammar of Graphics].
Solution for version 2: a dot . instead of data:
data %>%
filter(type=="type1") %>%
ggplot(., aes(x=year, y=variable)) +
geom_line()
I usually do this, which also dispenses with the need for the .:
library(dplyr)
library(ggplot2)
mtcars %>%
filter(cyl == 4) %>%
ggplot +
aes(
x = disp,
y = mpg
) +
geom_point()
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
