Positional is a location app that works on three important information of a specific region.
These three data comprise almost every piece of information shown in the app. Latitude and Longitude are a pair of fractional numbers and the Timezone is the ID of the region whose time offset is to be calculated. Using these three pieces of information carefully you can calculate an almost infinite amount of geological information of any region around the world and this is what makes this tool very powerful and also very flexible at the same time.
Once you click the Use Specified Coordinates in the Settings panel, a small window
will appear containing four input columns for Address, Latitude, Longitude
and Timezone (Timezone has been relocated to clock panel).
These four columns take the information as their name suggests and when you press
SET all these inputs will be saved to be used globally means anything you've
entered here will be used across every panel of the app and the information you've entered
will be used to calculate all the information such as Sun Position and Twilight.
Address column is optional and can be skipped if you don't know the information but the rest
three columns are compulsory but it is advisable to start the input from the address itself
because if the address is correct the app will fetch the Latitude and Longitude automatically
from the Geocoder's server and will save some time and user's efforts.
Although you can, you do not need to enter the full address of a particular region, small pieces
like region name, pin code, or a well known landmark will work too.
Coordinates are compulsory and are required in fractional number format meaning they should not
contain any special character, letter, or any Unicode character that is not a valid decimal
number.
The range of latitude is -90.0 to +90.0 likewise the range of longitude is -180.0 to +180.0 and
you can enter any number with as many decimal places as you want and it will be considered valid
as long as it falls within the specified range of the respective fields.
Time zone is compulsory, case-sensitive, and is limited to the options provided in the list so
it is recommended to select from the list only. The format of the timezone ID is fairly tricky
to use, it can be Continent/Region, UTC, and maybe GMT Offset and all of the options are
included inside the list.
Time zones are a powerful tool to use and when combined with coordinates it can be used as a
time reference of any region despite the region used in coordinates such as if you have used
Tokyo in address coordinates and selected the timezone of America/New_York the app will shift
all the time reference to the timezone of New York and will show like when the sun is going to
rise in Tokyo from the time reference of New York and if you have used Asia/Tokyo as timezone,
then it will show all the information of Tokyo using the time reference of Tokyo.
Hence it is very important to use timezones carefully else it can show misleading information
and lead to various miscalculations.
Although as a developer I crafted this application to be as easy to use as possible, this app
still expects some form of existing knowledge of how various location related information works,
how to correctly use timezone to get the correct time of the given region and various knowledge
of local and international standards of time and coordinates.
Wikipedia sources for some short readings