r - Create an empty data.frame

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Top 5 Answer for r - Create an empty data.frame

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Just initialize it with empty vectors:

df <- data.frame(Date=as.Date(character()),                  File=character(),                   User=character(),                   stringsAsFactors=FALSE)  

Here's an other example with different column types :

df <- data.frame(Doubles=double(),                  Ints=integer(),                  Factors=factor(),                  Logicals=logical(),                  Characters=character(),                  stringsAsFactors=FALSE)  str(df) > str(df) 'data.frame':   0 obs. of  5 variables:  $ Doubles   : num   $ Ints      : int   $ Factors   : Factor w/ 0 levels:   $ Logicals  : logi   $ Characters: chr  

N.B. :

Initializing a data.frame with an empty column of the wrong type does not prevent further additions of rows having columns of different types.
This method is just a bit safer in the sense that you'll have the correct column types from the beginning, hence if your code relies on some column type checking, it will work even with a data.frame with zero rows.

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If you already have an existent data frame, let's say df that has the columns you want, then you can just create an empty data frame by removing all the rows:

empty_df = df[FALSE,] 

Notice that df still contains the data, but empty_df doesn't.

I found this question looking for how to create a new instance with empty rows, so I think it might be helpful for some people.

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You can do it without specifying column types

df = data.frame(matrix(vector(), 0, 3,                 dimnames=list(c(), c("Date", "File", "User"))),                 stringsAsFactors=F) 
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You could use read.table with an empty string for the input text as follows:

colClasses = c("Date", "character", "character") col.names = c("Date", "File", "User")  df <- read.table(text = "",                  colClasses = colClasses,                  col.names = col.names) 

Alternatively specifying the col.names as a string:

df <- read.csv(text="Date,File,User", colClasses = colClasses) 

Thanks to Richard Scriven for the improvement

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Just declare

table = data.frame() 

when you try to rbind the first line it will create the columns

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