Using GSheets Script to increment value of duplicate by 1 - google-sheets

Question

I want to check a row for duplicates and if match increment these by 1.
The data I want to manipulate this way is LAT LONG Coordinates.
They originate from an aggregated data acquisition, where users can only insert country and city. Via an Add-On these will get GEO coded.
Problem is, that I need to slightly change the values of duplicate entries, in order to display them on a map. Easiest way (I think) is to increment a LAT or LONG coordinate by 1 if there is already an entry with the same value.
Data sample & results of script
Any idea how to do this via Script?
My code, originally intended to delete duplicate rows:
function overwriteDuplicates() {
var ss=SpreadsheetApp.getActive();
var sh=ss.getSheetByName("Formularantworten 2");
var vA=sh.getDataRange().getValues();
var hA=vA[0];
var hObj={};
hA.forEach(function(e,i){hObj[e]=i;});//header title to index
var uA=[];
var d=0;
for(var i=0;i<vA.length;i++) {
if(uA.indexOf(vA[i][hObj['Latitude']])==-1) {
uA.push(vA[i][hObj['Latitude']]);
}else{
function increment() {
SpreadsheetApp.getActiveSheet().getRange('K').setValue(SpreadsheetApp.getActiveSheet().getRange('K').getValue() + 1);
}
}}}

Answer 1

You want to modify the latitude whenever duplicate coordinates (latitude and longitude is found).
In this case, you can do the following:
Get all the values in the sheet, and retrieve the indexes where Latitude and Longitude are, based on the headers.
Loop through all rows (excluding headers), and for each row, check whether a previous row contains these coordinates.
If that's the case (isDuplicate), increment the last number in the latitude (after the last .), or decrement it if it's close to 999 (I assume there's always 3 digits).
Store the new latitude in an array after modification.
Use setValues to write the modified latitudes to the sheet.
Below is a possible code snippet to do this (see inline comments for details).
Code snippet:
function overwriteDuplicates() {
const ss = SpreadsheetApp.getActive();
const sheet = ss.getSheetByName("Formularantworten 2");
const values = sheet.getDataRange().getValues();
const headers = values.shift(); // Retrieve first row (headers)
const latColumn = headers.indexOf("Latitude"); // Latitude column index
const longColumn = headers.indexOf("Longitude"); // Longitude column index
let outputLocations = [];
for (let i = 0; i < values.length; i++) { // Loop through rows
const newLocation = { // Store object with current location
"latitude": values[i][latColumn],
"longitude": values[i][longColumn]
}
let isDuplicate;
do { // Check if location is duplicate, and increment if necessary
isDuplicate = outputLocations.some(location => {
const sameLatitude = location["latitude"] === newLocation["latitude"];
const sameLongitude = location["longitude"] === newLocation["longitude"];
return sameLatitude && sameLongitude;
});
if (isDuplicate) newLocation["latitude"] = modifyCoord(newLocation["latitude"]);
} while (isDuplicate);
outputLocations.push(newLocation); // Store new location in array
}
let outputLatitudes = outputLocations.map(location => [location["latitude"]]); // Retrieve latitudes from array
sheet.getRange(2, latColumn+1, sheet.getLastRow()-1).setValues(outputLatitudes); // Write updated latitudes to sheet
}
function modifyCoord(coordinates) {
let coordArray = coordinates.split(".");
let lastCoord = coordArray.pop();
if (lastCoord > 990) lastCoord--;
else lastCoord++;
coordArray.push(lastCoord);
return coordArray.join(".");
}
Output: