as.data.frame

R Base 3.6.2

Functions to check if an object is a data frame, or coerce it if possible.

Syntax

as.data.frame(x, row.names = NULL, optional = FALSE, &#8230;)<p></p><p># S3 method for character
as.data.frame(x, &#8230;,
              stringsAsFactors = default.stringsAsFactors())</p><p># S3 method for list
as.data.frame(x, row.names = NULL, optional = FALSE, &#8230;,
              cut.names = FALSE, col.names = names(x), fix.empty.names = TRUE,
              stringsAsFactors = default.stringsAsFactors())</p><p># S3 method for matrix
as.data.frame(x, row.names = NULL, optional = FALSE,
              make.names = TRUE, &#8230;,
              stringsAsFactors = default.stringsAsFactors())</p><p>is.data.frame(x)</p>

Arguments

Parameter	Description
`x`	any R object.
`row.names`	NULL or a character vector giving the row names for the data frame. Missing values are not allowed.
`optional`	logical. If TRUE, setting row names and converting column names (to syntactic names: see make.names) is optional. Note that all of R's base package as.data.frame() methods use optional only for column names treatment, basically with the meaning of data.frame(*, check.names = !optional). See also the make.names argument of the matrix method.
`…`	additional arguments to be passed to or from methods.
`stringsAsFactors`	logical: should the character vector be converted to a factor?
`cut.names`	logical or integer; indicating if column names with more than 256 (or cut.names if that is numeric) characters should be shortened (and the last 6 characters replaced by " ...").
`col.names`	(optional) character vector of column names.
`fix.empty.names`	logical indicating if empty column names, i.e., "" should be fixed up (in data.frame) or not.
`make.names`	a logical, i.e., one of FALSE, NA, TRUE, indicating what should happen if the row names (of the matrix x) are invalid. If they are invalid, the default, TRUE, calls make.names(*, unique=TRUE); make.names=NA will use “automatic” row names and a FALSE value will signal an error for invalid row names.

Return Value

as.data.frame returns a data frame, normally with all row names "" if optional = TRUE. is.data.frame returns TRUE if its argument is a data frame (that is, has "data.frame" amongst its classes) and FALSE otherwise.

Details

as.data.frame is a generic function with many methods, and users and packages can supply further methods. For classes that act as vectors, often a copy of as.data.frame.vector will work as the method. If a list is supplied, each element is converted to a column in the data frame. Similarly, each column of a matrix is converted separately. This can be overridden if the object has a class which has a method for as.data.frame: two examples are matrices of class "model.matrix" (which are included as a single column) and list objects of class "POSIXlt" which are coerced to class "POSIXct". Arrays can be converted to data frames. One-dimensional arrays are treated like vectors and two-dimensional arrays like matrices. Arrays with more than two dimensions are converted to matrices by ‘flattening’

as.data.frame

Syntax

Arguments

Return Value

Details

See Also