Pivot or Transpose data in a google sheet using apps script - google-apps-script

Question

I'm hoping someone can assist me with either pivoting or transposing data within a google sheet programmatically using apps script.
Below is what I've done so far. I'm pretty sure this is far from the correct/optimum way of achieving this hence me reaching out here. The data is for a survey with 3 questions. The script runs fine but doesn't account for any surveys where there where no answers selected for a certain question or for any one of the 3 questions. I'm pretty sure that's because there needs to be an else statement part of each If statement but can't figure out how to write that logic within each loop.
I also tried experimenting by converting this to and array of objects, where I tried using the ID key to to match the date, source, and three questions but couldn't get that working either.
I've attached images of what the source data looks like and what I'm trying to achieve, as well as what it currently looks like after I execute the script I currently have.
The code I've written is after the 3 images I've uploaded.
Hope I've explained this all correctly. I'd appreciate any assistance with this.
The source data looks like this:
And this is what I am trying to achieve:
This is what the data looks like once the above code has run:
function sample() {
var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheet = ss.getSheetByName('sampleData');
var range = sheet.getRange(2,1,sheet.getLastRow()-1,sheet.getLastColumn());
var values = range.getValues();
var resultsSh = ss.getSheetByName('sampleResults');
//console.log(values);
var source = values.filter(function(row){
if(row[2] === 'Source'){
return true;
} else {
return false;
}
});
//console.log(source);
var q1 = values.filter(function(row){
if(row[2] === 'Question1'){
return true;
} else {
return false;
}
});
//console.log(q1);
var q2 = values.filter(function(row){
if(row[2] === 'Question2'){
return true;
} else {
return false;
}
});
//console.log(q2);
var q3 = values.filter(function(row){
if(row[2] === 'Question3'){
return true;
} else {
return false;
}
});
//console.log(q3);
var result1 = [];
for (i=0;i<source.length;i++){
for (j=0;j<q1.length;j++){
if(source[i][1] === q1[j][1]){
result1.push([...source[i], ...q1[j]]);
}
}
}
//console.log(result1);
var result2 = [];
for (i=0;i<result1.length;i++){
for (j=0;j<q2.length;j++){
if (result1[i][1] === q2[j][1]) {
result2.push([...result1[i],...q2[j]])
}
}
}
//console.log(result2);
var final = [];
for (i=0;i<result2.length;i++) {
for (j=0;j<q3.length;j++) {
if (result2[i][1] === q3[j][1]) {
final.push([...result2[i], ...q3[j]])
}
}
}
//console.log(final);
var data = final.map(function(row){
return [row[0].toLocaleString('en-GB').replace(/[',']/g,''), row[1], row[3], row[7], row[11], row[15], row[7] + row[11] + row[15]];
});
console.log(data);
ss.getSheetByName('Sheet16').getRange(2, 1, data.length, data[0].length).setValues(data);
}

Answer 1

This can be done with a single for loop that checks each row and a switch() case: to fill up the respective array elements and compute for the sum.
function sample() {
var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheet = ss.getSheetByName('sampleData');
var range = sheet.getRange(2,1,sheet.getLastRow()-1,sheet.getLastColumn());
var values = range.getValues();
var resultsSh = ss.getSheetByName('sampleResults');
var lastRow = sheet.getLastRow();
var lastID = values[0][1];
var result = [];
var sum = 0;
// check each row
for (i=0; i<lastRow-1; i++) {
var currID = values[i][1];
if ((currID != lastID) & sum) {
result[result.length-1] = sum;
}
switch (values[i][2]) {
case 'Source':
result.push(values[i][0],values[i][1],values[i][3],'','','','');
sum = 0;
break;
case 'Question1':
result[result.length-4] = values[i][3];
sum += values[i][3];
break;
case 'Question2':
result[result.length-3] = values[i][3];
sum += values[i][3];
break;
case 'Question3':
result[result.length-2] = values[i][3];
sum += values[i][3];
break;
}
lastID = currID;
}
result[result.length-1] = sum;
// convert to 2d array
const result2d = [];
while(result.length) result2d.push(result.splice(0,7));
// put to results sheet
var resultRange = resultsSh.getRange(2,1,result2d.length,result2d[0].length);
resultRange.setValues(result2d);
}
Sample Data:
Sample Results: