Time series label in R

Question

I have a dataframe in R where:

Date        MeanVal

2002-01     37.70722
2002-02     43.50683
2002-03     45.31268
2002-04     14.96000
2002-05     29.95932
2002-09     52.95333
2002-10     12.15917
2002-12     53.55144
2003-03     41.15083
2003-04     21.26365
2003-05     33.14714
2003-07     66.55667
 .
 .
2011-12     40.00518

And when I plot a time series using ggplot with:

ggplot(mean_data, aes(Date, MeanVal, group =1)) + geom_line()+xlab("") 
+ ylab("Mean Value")

I am getting:

but as you can see, the x axis scale is not very neat at all. Is there any way I could just scale it by year (2002,2003,2004..2011)?

It's likely your `Date` variable is a character class here given its format. I'd suggest converting it to a Date class and then plotting. — zack, Apr 16 '19 at 14:46
@zack I tried df$Date <- as.Date(df$Date, format="%Y-%m"), it becomes once i do so. — Maxxx, Apr 16 '19 at 14:58
this should work: `df$Date <- lubridate::ymd(paste0(df$Date, "-01"))`, you'll need to have installed the `lubridate` package at some point. — zack, Apr 16 '19 at 15:09
Maybe a dupe of this: https://stackoverflow.com/q/11547414/5325862 — camille, Apr 16 '19 at 15:15

score 2 · Answer 1 · answered Apr 16 '19 at 15:02

Let's use lubridate's parse_date_time() to convert your Date to a date class:

library(tidyverse)
library(lubridate)

mean_data %>% 
  mutate(Date = parse_date_time(as.character(Date), "Y-m")) %>%
  ggplot(aes(Date, MeanVal)) +
  geom_line()

Similarly, we can convert to an xts and use autoplot():

library(timetk)

mean_data %>% 
  mutate(Date = parse_date_time(as.character(Date), "Y-m")) %>%
  tk_xts(silent = T) %>% 
  autoplot()

This achieves the plot above as well.

Odysseus210 · Answer 2 · 2019-04-16T16:48:23.930

0

library(dplyr)

mean_data %>%
  mutate(Date = as.integer(gsub('-.*', '', Date)) %>% 
  #use the mutate function in dplyr to remove the month and cast the 
  #remaining year value as an integer
  ggplot(aes(Date, MeanVal, group = 1)) + geom_line() + xlab("") 
    + ylab("Mean Value")

edited Apr 16 '19 at 16:48

answered Apr 16 '19 at 15:08

Odysseus210

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3
9

While this code may answer the question, providing additional context regarding why and/or how this code answers the question improves its long-term value. – Donald Duck Apr 16 '19 at 16:13

Time series label in R

2 Answers2