Saving SQLite list as an array: Not Working

I have an SQLite Database, and within it, one of the columns stores Strings which include numbers. I am trying to retrieve the numbers, store them as doubles in an array, and then take the mean of the array. However, it's not working. The App crashes every time I get to that part. I know the problem has to be somewhere within the array because I am able to list the SQLite Database as a string.

public int getDataCount() {
    String countQuery = "SELECT * FROM " + TABLE_PRODUCTS + " WHERE 1";
    SQLiteDatabase db = this.getReadableDatabase();
    Cursor cursor = db.rawQuery(countQuery, null);
    int cnt = cursor.getCount();
    cursor.close();
    return cnt;
}


public double databaseAverage(){
    String dbString = "";
    int dbInt = 0;
    double dbDouble = 0;

    SQLiteDatabase db = getWritableDatabase();
    String query = "SELECT * FROM " + TABLE_PRODUCTS + " WHERE 1";

    Cursor c = db.rawQuery(query, null);
    c.moveToFirst();

    int rowCount = getDataCount();

    Double[] array = new Double[rowCount];
    int i = 0;

    while (!c.isAfterLast()) {
        if (c.getString(c.getColumnIndex("productname")) != null) {
            dbString += c.getString(c.getColumnIndex("productname"));

            dbInt = Integer.parseInt(dbString.replaceAll("[\\D]",""));


            dbDouble = (double) dbInt;


            array[i] = dbDouble;
            i++;

        }
        c.moveToNext();
    }
    db.close();


    double sum = 0;

    for(int v=0; v < array.length ; v++) {
        sum = sum + array[i];
    }

    double average = sum / array.length;

    return average;

}