How to plot all the values in a row with barplot in R?-CodePudding

I have this csv file:

a,b,c,d,e
1,5,9,13,17
2,6,10,14,18
3,7,11,15,19
4,8,12,16,20

I name it data.csv. Then I write the following script.

data <- read.csv('data.csv')
row <- data[2,]
row
dput(head(row))
barplot(row)

The output is the following:

$ Rscript testing.R
  a b  c  d  e
2 2 6 10 14 18
Error in barplot.default(row) : 'height' must be a vector or a matrix
Calls: barplot -> barplot.default
Execution halted

This doesn't happen with columns, i.e., if I use row <- data[,2]. I get the following with this:

$ Rscript testing.R
[1] 5 6 7 8

How do I plot all the numbers in a row like I do for columns?

CodePudding user response：

When extracting a column of a data frame, we automatically get a verctor.

is.vector(dat[, 2])
# [1] TRUE

When we extract the row of a data frame, we still have a "data.frame" which we want to unlist in order to get the desired vector.

is.vector(dat[2, ])
# [1] FALSE

is.vector(unlist(dat[2, ]))
# [1] TRUE

Therefore you need to do this:

barplot(unlist(dat[2, ]))

Data:

data <- read.csv(text='a,b,c,d,e
1,5,9,13,17
2,6,10,14,18
3,7,11,15,19
4,8,12,16,20
')