Convert string to variable name in R

Question

I have spend hours to look for a proper solutions but I found nothing on Internet. There is my question. In R, I have a specific list of characters containings my desired variable names ("2011_Q4", "2012_Q1", ...). When I try to assign a dataset to each of this name with a loop, it does work but the output it's strange. Indeed, I have

> View(`2011_Q4`)

instead of

> View(2011_Q4)

And I don't know how to remove this apostrophe. It's very annoying since I have to type this ` in order to call the variable.

Somebody can help me? I would appreciate his help.

Thanks a lot and best regards

Answer 1

Firstly, it's a backtick (`), not an apostrophe ('). In R, backticks occasionally denote variable names; apostrophes work as single quotes for denoting strings.

The issue you're having is that your variables start with a number, which is not allowed in R. Since you somehow made it happen anyway, you need to use backticks to tell R not to interpret 2011_Q4 as a number, but as a variable.

From ?Quotes :

Names and Identifiers

Identifiers consist of a sequence of letters, digits, the period (.) and the underscore. They must not start with a digit nor underscore, nor with a period followed by a digit. Reserved words are not valid identifiers.

The definition of a letter depends on the current locale, but only ASCII digits are considered to be digits.

Such identifiers are also known as syntactic names and may be used directly in R code. Almost always, other names can be used provided they are quoted. The preferred quote is the backtick (`), and deparse will normally use it, but under many circumstances single or double quotes can be used (as a character constant will often be converted to a name). One place where backticks may be essential is to delimit variable names in formulae: see formula.

The best solution to your issue is simply to change your variable names to something that starts with a character, eg Y2011_Q4 .