[Google Scripts] Replace commas with dots in Google Spreadsheets

script.js

function replaceCommasDots() {
  var id = ''; /* Your spreadsheet id (value after /id/*): https://docs.google.com/spreadsheets/d/:id/edit */
  var sheet = SpreadsheetApp.openById(id);
  var range = sheet.getRange("A1:B2"); /* range you want to modify */
  var data  = range.getValues();

  for (var row = 0; row < data.length; row++) {
    for (var col = 0; col < data[row].length; col++) {
      data[row][col] = (data[row][col]).toString().replace(/,/g, '.');
    }
  }
  range.setValues(data);
}