Error in plotting atomic vector - r

Question

I want to plot log return graph. I imported my data file in CSV format.My code after that as below with the errors. For more information all the variables do exist in the table.
t <- read.csv("~/Documents/FYP/Log return 1.csv")
View(t)
df<-ts(t)
plot.ts(df$Year,df$IND)
Error in df$Year : $ operator is invalid for atomic vectors
plot.ts(df[Time],df[CHN])
Error in NextMethod("[") : object 'Time' not found
plot.ts(df[Year],df[CHN])
Error in NextMethod("[") : object 'Year' not found
plot.ts(df[[Year]],df[[CHN]])
Error in NCOL(x) : object 'Year' not found

Answer 1

Given a data frame input t, df <- ts(t) gives you a matrix rather than a data frame, so using $ is invalid. To access a column of a matrix, you need
for example, df[, "Time"].
As an example, let's use R's built-in dataset cars. Originally it is a data frame with two columns: speed and dist, while x <- ts(cars) gives a matrix:
class(x)
# [1] "mts" "ts" "matrix"
head(x)
# speed dist
#[1,] 4 2
#[2,] 4 10
#[3,] 7 4
#[4,] 7 22
#[5,] 8 16
#[6,] 9 10
The error you saw can be reproduced by
x$dist
# Error in x$dist : $ operator is invalid for atomic vectors
Instead, we want
x[, "dist"]
#Time Series:
#Start = 1
#End = 50
#Frequency = 1
# [1] 2 10 4 22 16 10 18 26 34 17 28 14 20 24 28 26 34 34 46
#[20] 26 36 60 80 20 26 54 32 40 32 40 50 42 56 76 84 36 46 68
#[39] 32 48 52 56 64 66 54 70 92 93 120 85