"(list) object cannot be coerced to type 'double'" error

[캉태준]

So, here's the thing, I'm integrating the R on my node project, however, I don't know how to import data properly from nodejs to R-script. I've been trying in forever.

Here's my latest code:

admin.js

 var R = require("r-script");

 var getSales = function() {
  const db = require('../db.js')
   let sql = `SELECT total_sales FROM sales_tbl`

  db.query(sql, (error, results, fields) => {
      if (error) throw error
      console.log(results);

      var dataframe = results.map(a => a.total_sales);
      dataframe = JSON.stringify(dataframe)
       dataframe = dataframe.slice(1, -1)

       console.log(dataframe);

      var out = R("./public/salesforecast.R")
           .data(dataframe)
           .callSync();

       console.log(out);
       return out
   })
}

salesforecast.R

` # salesforecast.R

 x <- (input)
 s <- as.numeric(12)
 numfore <- as.numeric(12)

x <- ts(x, frequency = s)
fit <- HoltWinters(x, seasonal = 'additive')

p <- predict(fit, numfore, prediction.interval = TRUE) `

The error coming out is

/home/pauljohn/workspace/the-sims-project/node_modules/mysql/lib/protocol/Parser.js:80
throw err; // Rethrow non-MySQL errors
^
Error in R script ./public/salesforecast.R
‘(list) object cannot be coerced to type 'double'’