What is the correct syntax for an IF statement in a FOR loop?

I am trying to populate an array with the combined values of two other arrays and am trying to use a for loop to do so.

var filterTables = ["1","2","3"]
var filterValues = ["Egypt",,"Ghana"]

for (i = 0; i < filterValues.length ; i++) {        
  if (filterValues[i]) { 
    for (i = 0; i < filterValues.length ; i++) {
      var filter = '{field: '+filterTables[i]+',value:'+filterValues[i]+',operator:"="},'
       filterArray.filters.push(filter)       
      if (i===3) {
         '{field: "'+filterTables[i]+'",value:"'+filterValues[i]+'",operator:"="}'
      }
    }
  } 
}

But the FOR loop isn't executing at all and I think it is because of the first IF statement that checks if there is a value in the current [i] position. Is it being used correctly? Do I need an IF statement outside of the FOR loop?

This is the desired result:

var filter = '{field: '1',value:'Egypt',operator:"="}'
var filter = '{field: '3',value:'Ghana',operator:"="}'