将CSV文件导入到R-读取为字符的因子

Question

New to R. When importing a csv file columns are being read as characters when they are in fact - or should be - factors. All three columns in question have only two levels (yes/no and male/female).

My attempt: In the Import Text Data dialog box I change the the columns to factor by inserting a comma separated list of factors.

> LungCapDataCSVnew <- read_csv("~/file.csv", 
  col_types = cols(Caesarean = col_factor(levels = c("no", 
  "yes")), Gender = col_factor(levels = c("male", 
  "female")), Smoke = col_factor(levels = c("no", 
  "yes"))))

> View(file)

> class(Gender)
[1] "character"

> class(Smoke)
[1] "character"

As it shows, 'Gender' and 'Smoke' columns read as characters when they should be factors.

How to solve this?

Answer 1

It's strange that simply read.csv() without any extra arguments doesn't automatically read in your characters as factors.

After importing the file with file <- read.csv("~/file.csv") you can try

i <- sapply(file, is.character)
file[i] <- lapply(file[i], as.factor)

To convert all character columns into factors

Answer 2

Use can change character into factor

LungCapDataCSVnew$Smoke<-as.factor(LungCapDataCSVnew$Smoke)
LungCapDataCSVnew$Gender<-as.factor(LungCapDataCSVnew$Gender)

New to R . Suggesting website- http://cran.r-project.org/manuals.html

Thanks

Answer 3

正如我刚刚发现的那样：read.csv似乎可以检测到因素和级别read_csv不会，它只是将列标题分配为字符。