Histogram in R. Problem with Function hist()

Question

I have csv file with ID and variable. It looks like this

    ID   V1
    1    0
    2   -0,12
    3    0,05
    ....

if I use hist(mydata$V1) I get an error message

Error in hist.default(mydata$V1) : 'x' must be numeric

But with variable ID (mydata$ID) it works. What is bad with variable V1, 0 at first place? Thanks!

Answer 1

What is bad with variable V1, 0 at first place?

It must be numeric. Looks like you've got some commas in there and R is considering it to be a factor or character type column.

Try

hist(table(mydata$V1))

or

barplot(table(mydata$V1))

to get a histogram of the resulting factor.

Check out this question if your goal is to read in the column as numeric, interpreting the comma as a decimal separator.

Answer 2

不知道为什么，但是当我手动从数据集中导入数据并将编码从自动更改为UTF时，它可以工作。