R help - Oct 2017 - data.matrix output is not numeric

I have a data frame full of integer values.  I need a matrix full of
numeric values.

?data.matrix reads:

     Return the matrix obtained by converting all the variables in a
     data frame to numeric mode and then binding them together as the
     columns of a matrix.

This does not work.

test.df <- data.frame(a=as.integer(c(1,2,3)),
b=as.integer(c(4,5,6)))
> class(test.df[[1,1]])
[1] "integer"
> class(data.matrix(test.df)[[1]])
[1] "integer"

What's going on here?

integer is a subclass of numeric.
> is.numeric(data.matrix(test.df)[[1]])
[1] TRUE

See  ?integer, ?numeric, ?storage.mode

On Fri, Oct 13, 2017 at 2:07 PM, Ed Siefker <ebs15242 at gmail.com>
wrote:
> I have a data frame full of integer values.  I need a matrix full of
> numeric values.
>
> ?data.matrix reads:
>
>      Return the matrix obtained by converting all the variables in a
>      data frame to numeric mode and then binding them together as the
>      columns of a matrix.
>
> This does not work.
>
> test.df <- data.frame(a=as.integer(c(1,2,3)), b=as.integer(c(4,5,6)))
>> class(test.df[[1,1]])
> [1] "integer"
>> class(data.matrix(test.df)[[1]])
> [1] "integer"
>
> What's going on here?
>
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