R +中的时间序列图帮助需要将月份和年份列合并

Question

I am having issues combining the month and year column into a date format

n month year Score
35 01 2013 1.07
29 02 2013 3.09
31 03 2013 1.08
.....

I have made the following attempts but just get a column of NAs:

df$date <- as.Date(with(df, paste(df$year, df$month,sep="-")), "%Y-%m")

df$Date <- with(df, sprintf("%Y-%m", year, month))

df$Date <- as.yearmon(paste(df$year, df$month), "%Y %m")

I am also struggling with creating a time series bar chart with "Score" data as the bars and "n" data plotting the line graph on the same axis

NB

lapply(df, class)

shows an output of

$n
[1] "integer"

$month
[1] "character"

$year
[1] "character"

$Score
[1] "numeric"

Answer 1

For as.Date to make a valid date you need to supply a day as well.

Test data

df = read.table(text = "n month year Score
35 01 2013 1.07
29 02 2013 3.09
31 03 2013 1.08", header = TRUE, sep = " ")
df$month = paste0("0", df$month)

Conversion

df$date <- as.Date(paste(df$year, df$month, "01", sep="-"), "%Y-%m-%d")
>df$date
[1] "2013-01-01" "2013-02-01" "2013-03-01"

Plot

Your score and n values are too different to plot at the same scale on the same chart:

library(ggplot2)
ggplot(data = df, aes(x = date, y = Score)) + 
  geom_col(fill = "gray60") + 
  geom_line(aes(y = n))

You could normalise the scale, for example by dividing the y values by the maximum for the score and n components respectively (perhaps labelling the bars and points on each chart with their actual values), or separate your plots, or take some other action which allows you to plot both when they are so dissimilar I leave this to you to decide.