如何查看 .RData 文件中的数据？

Question

I saw some similar qestions and I tried to work it out on my own, but I couldn't. This is my problem:

I have to load a isfar.RData file to use it in other computation (which are not important to describe here). And I would like to simply see how looks data in this isfar.RData file eg what numbers, columns, rows it carries.

First I load my file:

isfar<-load("C:/Users/isfar.RData") 

When I try to obtain this information (I'm using Rcmdr) by ls() function or marking isfar at the beginning after loading I get in the output window: [1] "isfar" instead of the table. Why?

Thanks a lot, I appreciate all of the answers! Hope it's comprehensible what I wrote, Im not a native speaker.

Answer 1

I think the problem is that you load isfar data.frame but you overwrite it by value returned by load .

Try either:

load("C:/Users/isfar.RData") 
head(isfar)

Or more general way

load("C:/Users/isfar.RData", ex <- new.env())
ls.str(ex) 

Answer 2

you can try

isfar <- get(load('c:/users/isfar.Rdata'))

this will assign the variable in isfar.Rdata to isfar . After this assignment, you can use str(isfar) or ls(isfar) or head(isfar) to get a rough look of the isfar.

Answer 3

Look at the help page for load . What load returns is the names of the objects created, so you can look at the contents of isfar to see what objects were created. The fact that nothing else is showing up with ls() would indicate that maybe there was nothing stored in your file.

Also note that load will overwrite anything in your global environment that has the same name as something in the file being loaded when used with default behavior. If you mainly want to examine what is in the file, and possibly use something from that file along with other objects in your global environment then it may be better to use the attach function or create a new environment ( new.env ) and load the file into that environment using the envir argument to load .

Answer 4

This may fit better as a comment but I don't have enough reputation, so I put it here.
It worth mentioning that the load() function will retain the object name that was originally saved no matter how you name the .Rdata file.

Please check the name of the data.frame object used in the save() function . If you were using RStudio, you could check the upper right panel, Global Environment-Data, to find the name of the data you load.

Answer 5

If you have a lot of variables in your Rdata file and don't want them to clutter your global environment, create a new environment and load all of the data to this new environment.

load(file.path("C:/Users/isfar.RData"), isfar_env <- new.env() )

# Access individual variables in the RData file using '$' operator
isfar_env$var_name 

# List all of the variable names in RData:
ls(isfar_env)

Answer 6

You can also import the data via the "Import Dataset" tab in RStudio, under "global environment." Use the text data option in the drop down list and select your .RData file from the folder. Once the import is complete, it will display the data in the console. Hope this helps.

Answer 7

It sounds like the only varaible stored in the .RData file was one named isfar .

Are you really sure that you saved the table? The command should have been:

save(the_table, file = "isfar.RData")

---

There are many ways to examine a variable.

Type it's name at the command prompt to see it printed. Then look at str , ls.str , summary , View and unclass .

Answer 8

num <- seq(0, 5, length.out=10) #create object num
num
[1] 0.00 1.25 2.50 3.75 5.00
save(num, file = 'num.RData') #save num ro RData
rm(num) #remove num 
load("num.RData") #load num from RData
num
[1] 0.00 1.25 2.50 3.75 5.00

> isfar<-load("num.RData")
> typeof(isfar)
 [1] "character"
> isfar  #list objects saved in RData
 [1] "num"

Answer 9

You don't seem to need to assign it to a variable. That bit magically happens...

get(load('C:/Users/isfar.Rdata'))

Or if it's in the same folder as your R code...

get(load('isfar.Rdata'))

Answer 10

isfar<-load("C:/Users/isfar.RData") 
if(is.data.frame(isfar)){
   names(isfar)
}

If isfar is a dataframe, this will print out the names of its columns.