Restrict map() to only run on a list of headers in an array made from a range

Question

I want to restrict the map to only those columns of the range that are in the list headers which is a subset of v[0] so that only the values in the columns of the range listed in headers are changed.

function test() {
  var ss  = SpreadsheetApp.getActiveSpreadsheet();  
  var sht = ss.getSheetByName('Elements');  
  var rng = sht.getDataRange();
  var v   = rng.getValues();
  
  var headers = ['Id', 'Label'];
  //headers is a subset of v[0]
  

  //This will work for `all` values of the values
  //values = v.map(x => x.map(y => y==("Networking - 1") ? 1: y));

  values = v.map(x => x.map(y => y== cols.includes(y)==true && y=="Networking - 1" ? 1: y))
  
  var sht2 = ss.getSheetByName('AAA');
  sht2.getRange(1,1, v.length, v[0].length).setValues(v);
}

Answer 1

Explanation:

• The first step is to get the column indexes where headers appears. To do that, you can apply indexOf to the first row of your data v which is the headers row:

  v[0].indexOf(headers[0])
  v[0].indexOf(headers[1])
  

• The next step is to use map to get only these columns:

  v.map(d=>[d[v[0].indexOf(headers[0])],d[v[0].indexOf(headers[1])]]);
  

Solution:

function test() {
  var ss  = SpreadsheetApp.getActiveSpreadsheet();  
  var sht = ss.getSheetByName('Elements');  
  var rng = sht.getDataRange();
  var v   = rng.getValues();
  
  
  var headers = ['Id', 'Label'];
  //headers is a subset of v[0]
  
  v = v.map(d=>[d[v[0].indexOf(headers[0])],d[v[0].indexOf(headers[1])]]); // new code

  //This will work for `all` values of the values
  //values = v.map(x => x.map(y => y==("Networking - 1") ? 1: y));

  values = v.map(x => x.map(y => y== cols.includes(y)==true && y=="Networking - 1" ? 1: y))
  
  var sht2 = ss.getSheetByName('AAA');
  sht2.getRange(1,1, v.length, v[0].length).setValues(v);
}