How to coerce a list object to type double

Question

The code   a  lt - structure list  X Days    c  10    38    66    101    129    185    283                                      374      Names    X Days     Then a is like    X Days   1   10    38    66    101   129   185   283   374    I would like to coerce a to an array of numeric values  but coercing functions return me  Error   list  object cannot be coerced to type  double    Thanks

User · Accepted Answer

If you want to convert all elements of a to a single numeric vector and length a  is greater than 1  OK  even if it is of length 1   you could unlist the object first and then convert   as numeric unlist a      1   10  38  66 101 129 185 283 374   Bear in mind that there aren t any quality controls here  Also  X Days a mighty odd name

User · Answer

There are problems with some data  Consider   as double as character  2 e      This results in 2   Another solution   get numbers  lt - function X        X toupper X     tolower X    lt - NA     return as double as character X

User · Answer

You can also use list subsetting to select the element you want to convert  It would be useful if your list had more than 1 element    as numeric a  1

User · Answer

In this case a loop will also do the job  and is usually sufficiently fast     a  lt - array 0  dim dim X   for  i in 1 ncol X    a  i   lt - X  i

User · Answer

If your list as multiple elements that need to be converted to numeric  you can achieve this with lapply a  as numeric

[r] How to coerce a list object to type 'double'

Examples related to r