GAS: How to create a globally accessible Array variable across multiple functions - arrays

Question

So, I have been asked to rephrase my question post. I actually thought it would make sense if I shared a picture of what I need to accomplish. My apologies for not knowing the format. But anywho ...
Required:
I have a spreadsheet file and a user enters a value in a specific cell (see picture below). I want that value be stored along with the current date in a two dimensional array.
What my code does: This code is
(1) Using a PropertiesService to store a value globally
(2) Accepting user input in H3 cell and is updating J3 cell with a date of format mm/dd and appending the user input. For e.g., if user inputs 4 in H3 and current date is 8/29/2019, then J3 will display "8/29::4"
(3) This code also adds a comment with the above value in H3
Error/Issue
(1) When I try to declare an array in the onEdit function and attempt to write something into it, it is spitting this error:
TypeError: Cannot read property 'push' of undefined
at onEdit(Code:21:29)
var scriptProperties = PropertiesService.getScriptProperties();
scriptProperties.setProperty('i', 0);
function onEdit(e){
if (e.range.getA1Notation() == "H3")
{
var difference = isNaN(e.value) ? 0 : Number(e.value);
var date = (new Date());
var monthValue = date.getMonth();
var dateValue = date.getDate();
var wholeValues = [];
monthValue = monthValue+1;
dateValue = dateValue-1;
var logTimestamp = monthValue+"/"+dateValue;
e.range.getSheet().getRange("J3").setValue(logTimestamp+"::"+difference+";");
e.range.setNote(logTimestamp+"::"+difference+";");
var arrayIndex = Number(scriptProperties.getProperty('i'));
wholeValues[arrayIndex].push("Sample Data");
arrayIndex = arrayIndex + 1;
Logger.log("wholeValues size is " +wholeValues.length);
}
}

Answer 1

Issues:
wholeValues array is local and won't persist across sessions/function calls/script runs.
wholeValues is a empty array all the time.
i will always be "0" as you're setting it to 0 in global scope each time a function is called.
wholeValues[0](=[][0]) is undefined as there is no element with index 0. undefined doesn't have .push function. Therefore, Cannot read property 'push' of undefined
Solution:
Different approaches can be made:
Create a object dateObj with value {date1:value1,date2:value2,...} and store it in properties as a string.
Set the datestring itself as a key to properties. Here each property is object containing {date:value}
You can save the array in a log sheet.
Snippet:
/*var scriptProperties = PropertiesService.getScriptProperties();
scriptProperties.setProperty('i', 0);*/ //Removed from global scope
function onEdit(e){
if (e.range.getA1Notation() == "H3")
{
/* Rest of your code*/
e.range.setNote(logTimestamp+"::"+difference+";");
var scriptProperties = PropertiesService.getScriptProperties();
var dateObjStr = scriptProperties.getProperty('dateObj');
var dateObj = dateObjStr ? JSON.parse(dateObjStr) : {};
var dateStr = Utilities.formatDate(date, e.source.getSpreadsheetTimeZone(), "YYYY-MM-dd");
dateObj[dateStr] = difference;//{"2019-08-28": 6}
scriptProperties.setProperty('dateObj', JSON.stringify(dateObj));
}
}
Snippet#2:
var scriptProperties = PropertiesService.getScriptProperties();
var dateStr = Utilities.formatDate(date, e.source.getSpreadsheetTimeZone(), "YYYY-MM-dd");
scriptProperties.setProperty(dateStr, difference);
var dateVal = scriptProperties.getProperty(dateStr) || 0; //Retrieval
Snippet#3:
var dateStr = Utilities.formatDate(date, e.source.getSpreadsheetTimeZone(), "YYYY-MM-dd");
e.source.getSheetByName('LogSheet').appendRow([dateStr, difference]);
References:
Quotas
Properties value size 9kB / val
Properties total storage 500kB / property store
Properties read/write 50,000 - 500,000/ day
PropertiesService
Utilities#formatDate