Change order of dates in R ggplot?

Question

I have been working on a plot in R using ggplot and plotting dates on the x axis. I have noticed that R does not recognize them as dates, and so the order on the x axis is wrong. I have tried many different things such as using as.Date(), manually editing levels and ordering the x axis, but nothing has worked. Here's my code:

library(dplyr)
library(ggplot2)
library(hrbrthemes)

calories_data = read.csv('dailyCalories_clean.csv',header = TRUE, sep=",")

ggplot(calories_data, aes(x= ActivityDay, y=Calories, group=Id, color = Id))+
  geom_line()

Here's the plot

I appreciate any help, I'm new at this and have been researching for hours with no success. Thank you!

Welcome to SO! It would be easier to help you if you provide [a minimal reproducible example](https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example) including a snippet of your data or some fake data. If you want to post your data type `dput(NAME_OF_DATASET)` into the console and copy the output starting with `structure(....` into your post. If your dataset has a lot of observations you could do e.g. `dput(head(NAME_OF_DATASET, 10))` for the first ten rows of data. — stefan, Jun 23 '22 at 15:06

score 0 · Accepted Answer · answered Jun 23 '22 at 15:13

One option to fix your issue would be to convert your dates to proper dates to fix the order and use the date_labels argument of scale_x_date to format your dates. To convert to dates you have to add a fake year to your ActivityDay, e.g. "2022":

Using some fake random data to mimic your real data:

library(ggplot2)

set.seed(123)

calories_data <- data.frame(
  ActivityDay <- rep(c("4/1", "4/10", "5/11", "5/1"), 3),
  Id = rep(1:3, each = 4),
  Calories = runif(12, 1000, 3000)
)

calories_data$ActivityDay <- as.Date(paste("2022", calories_data$ActivityDay, sep = "/"), format = "%Y/%m/%d")

ggplot(calories_data, aes(x= ActivityDay, y=Calories, group=Id, color = Id))+
  geom_line() +
  scale_x_date(date_breaks = "5 day", date_labels = "%m/%d")

Change order of dates in R ggplot?

1 Answers1