Free longitude software for linux

Global Village project is a gnome application designed to place a front-end, or graphical user interface onto the CLI interface of Xplanet, by Hari Nair.
Originally intended to create and update the desktop wallpaper in a gnome environment, showing a traditional rectangular projection of the planet Earth, the scope of the project has been expanded. Global Village now provides as many of the features of Xplanet as seem reasonable, and with the ability for plugins the scope is nearly limitless. But do take it with a grain of salt...
Current Status
Currently, Global Village is barely functional. It can be considered in the pre-alpha stage of development.
It can currently show a preview of the final image, and then display that image on the desktop at user specified intervals (in seconds), and has an icon in the notification area of the Gnome panel.
Plugins are semi-working, but undergoing a lot of change as I decide what they do adn dont need to be capable of. The idea is that plugins will manage all the extra features users require, like cloudmaps, marker and arc files.
Main features:
- Select a planet.
- Select a projection.
- Bodys North Type.
- Rotate the bodys North Pole
- The Zoom level
- The Suns glare
- Latitude and Longitude, which can be set as:
- North Pole
- South Pole
- Equator
- Random Latitude and Longitude
- Or any number of user configerable locations.

Xplanet was inspired by Xearth, which renders an image of the earth into the X root window. All of the major planets and most satellites can be drawn, similar to the Solar System Simulator.
A number of different map projections are also supported, including azimuthal, Lambert, Mercator, Mollweide, orthographic, and rectangular.
Enhancements:
- Added the -grs_longitude option, to specify the longitude of Jupiters Great Red Spot, in System II coordinates. This assumes the Jupiter image has the center of the Great Red Spot at pixel 0 (at the left side of the image) in order to draw it at the right position.
- Added the Icosagnomonic projection, contributed by Ian Turner.
- Fixed a bug where output filenames had an extra digit in some cases.
- Added the bump_map and bump_scale options in the configuration file.
- Added the -glare option to set the size of the suns glare.
- An image map may be specified for the sun in the configuration file now. A shade value is now required for the sun (should be 100, otherwise the sun will have a night side!)
- Added the -arc_spacing option to set the default angular distance between great arc points. It used to be 0.1 degree, so arcs smaller than this wouldnt get drawn.
- Fixed a bug where markers were not aligned properly when using align = "above" or "below".
- Added warnings if options are specified in the [default] section of the configuration file that probably shouldnt be there.

Geography::NationalGrid::TW is a Perl module to convert Taiwan Datum (TWD67/TM2, TWD97/TM2) to/from Latitude and Longitude.

SYNOPSIS

You should _create_ the object using the Geography::NationalGrid factory class, but you still need to know the object interface, given below.
# default TWD97
my $point1 = new Geography::NationalGrid::TW(
Easting => 302721.36,
Northing => 2768851.3995,
);
printf("Point 1 is %f X and %f Yn", $point1->easting, $point1->northing);
printf("Point 1 is %f N and %f En", $point1->latitude, $point1->longitude);
# transform to TWD67
$point1->transform(TWD67);

Once created, the object allows you to retrieve information about the point that the object represents. For example you can create an object using easting / northing and the retrieve the latitude / longitude.

GPS::Lowrance::Trail is a Perl module to convert between GDM16 Trails and other formats.

Installation:
Installation is pretty standard:
perl Makefile.PL
make
make test
make install

There is no test suite to speak of. One will be added in a later version.

SYNOPSIS
use GPS::Lowrance::Trail;

my $trail = new GPS::Lowrance::Trail;

my $fh1 = new FileHandle read_gdm16( $fh1 ); # read GDM16 Trail Exports

$trail->write_latlon( $fh2 ); # write as Longitude/Latitude file

This module allows one to convert between Lowrance GPS trail files (handled by their GDM16 application), Latitude/Longitude (or "Lat/Lon") files, UTM, and GPX files which may be used by mapping applications.

Xwota is intended for amateur radio operators who want to make use of the WOTA database.
Xwota can be used to find out who is on the air, the band and frequency they are operating on, and their location by country, state, county, grid, and latitude/longitude.
Enhancements:
- Query support.
- Private message autoanswer.
- Private message beep.
- Private messages saving.

Geo:Coder:US 1.00 offers a full-feature facility for geocoding US addresses, that is, estimating the latitude and longitude of any street address or intersection in the United States, using the TIGER/Line data set from the US Census Bureau. Geo:Coder:US uses Geo:TigerLine to parse this data, and DB_File to store a highly compressed distillation of it, and Geo:StreetAddress:US to parse addresses into normalized components suitable for looking up in its database.

You can find a live demo of this code at http://geocoder.us/. The demo.cgi script is included in eg/ directory distributed with this module, along with a whole bunch of other goodies. See Geo:Coder:US:Import for how to build your own Geo:Coder:US database.

Consider using a web service to access this geocoder over the Internet, rather than going to all the trouble of building a database yourself. See eg/soap-client.pl, eg/xmlrpc-client.pl, and eg/rest-client.pl for different examples of working clients for the rpc.geocoder.us geocoder web service.

Major Features:

1. Geo:Coder:US->geocode( $string )
   • Given a string containing a street address or intersection, return a list of specifiers including latitude and longitude for all matching entities in the database. To keep from churning over the entire database, the given address string must contain either a city and state, or a ZIP code (or both), or geocode() will return undef.
   • geocode() will attempt to normalize directional prefixes and suffixes, street types, and state abbreviations, as well as substitute TIGER/Line's idea of the "primary street name", if an alternate street name was provided instead.
   • If geocode() can parse the address, but not find a match in the database, it will return a hashref containing the parsed and normalized address or intersection, but without the "lat" and "long" keys specifying the location. If geocode() cannot even parse the address, it will return undef. Be sure to check for the existence of "lat" and "long" keys in the hashes returned from geocode() before attempting to use the values! This serves to distinguish between addresses that cannot be found versus addresses that are completely unparseable.
   • geocode() attempts to be as forgiving as possible when geocoding an address. If you say "Mission Ave" and all it knows about is "Mission St", then "Mission St" is what you'll get back. If you leave off directional identifiers, geocode() will return address geocoded in all the variants it can find, i.e. both "N Main St" and "S Main St".
   • Don't be surprised if geocoding an intersection returns more than one lat/long pair for a single intersection. If one of the streets curves greatly or doglegs even slightly, this will be the likely outcome.
   • geocode() is probably the method you want to use. See more in the following section on the structure of the returned address and intersection specifiers.
2. Geo:Coder:US->geocode_address( $string )
   • Works exactly like geocode(), but only parses addresses.
3. Geo:Coder:US->geocode_intersection( $string )
   • Works exactly like geocode(), but only parses intersections.
4. Geo:Coder:US->filter_ranges( $spec, @candidates )
   • Filters a list of address specifiers (presumably from the database) against a query specifier, filtering by prefix, type, suffix, or primary name if possible. Returns a list of matching specifiers. filter_ranges() will ignore a filtering step if it would result in no specifiers being returned. You probably won't need to use this.
5. Geo:Coder:US->find_ranges( $address_spec )
   • Given a normalized address specifier, return all the address ranges in the database that appear to cover that address. find_ranges() ignores prefix, suffix, and type fields in the specifier for search purposes, and then filters against them ex post facto. The intention for find_ranges() to find the closest match possible in preference to returning nothing. You probably want to use lookup_ranges() instead, which will call find_ranges() for you.
6. Geo:Coder:US->lookup_ranges( $address_spec, @ranges )
   • Given an address specifier and (optionally) some address ranges from the database, interpolate the street address into the street segment referred to by the address range, and return a latitude and longitude for the given address within each of the given ranges. If @ranges is not given, lookup_ranges() calls find_ranges() with the given address specifier, and uses those returned. You probably want to just use geocode() instead, which also parses an address string and determines whether it's a proper address or an intersection automatically.
7. Geo:Coder:US->find_segments( $intersection_spec )
   • Given a normalized intersection specifier, find all of the street segments in the database matching the two given streets in the given locale or ZIP code. find_segments() ignores prefix, suffix, and type fields in the specifier for search purposes, and then filters against them ex post facto. The intention for find_segments() to find the closest match possible in preference to returning nothing. You probably want to use lookup_intersection() instead, which will call find_segments() for you.
8. Geo:Coder:US->lookup_intersection( $intersection_spec )
   • Given an intersection specifier, return all of the intersections in the database between the two streets specified, plus a latitude and longitude for each intersection. You probably want to just use geocode() instead, which also parses an address string and determines whether it's a proper address or an intersection automatically.

Requirements: Perl

GIS::Distance::Vincenty Perl module contains Thaddeus Vincenty distance calculations.

SYNOPSIS

my $calc = GIS::Distance::Vincenty->new();
my $distance = $calc->distance( $lon1, $lat1 => $lon2, $lat2 );

For the benefit of the terminally obsessive (as well as the genuinely needy), Thaddeus Vincenty devised formulae for calculating geodesic distances between a pair of latitude/longitude points on the earths surface, using an accurate ellipsoidal model of the earth.

Vincentys formula is accurate to within 0.5mm, or 0.000015", on the ellipsoid being used. Calculations based on a spherical model, such as the (much simpler) Haversine, are accurate to around 0.3% (which is still good enough for most purposes, of course).

Note: the accuracy quoted by Vincenty applies to the theoretical ellipsoid being used, which will differ (to varying degree) from the real earth geoid. If you happen to be located in Colorado, 2km above msl, distances will be 0.03% greater. In the UK, if you measure the distance from Lands End to John O Groats using WGS-84, it will be 28m - 0.003% - greater than using the Airy ellipsoid, which provides a better fit for the UK.

NOTE: This formula is still considered alpha quality in GIS::Distance. It has not been tested enough to be used in production.

FORMULA

a, b = major & minor semiaxes of the ellipsoid
f = flattening (a-b)/a
L = lon2 - lon1
u1 = atan((1-f) * tan(lat1))
u2 = atan((1-f) * tan(lat2))
sin_u1 = sin(u1)
cos_u1 = cos(u1)
sin_u2 = sin(u2)
cos_u2 = cos(u2)
lambda = L
lambda_pi = 2PI
while abs(lambda-lambda_pi) > 1e-12
sin_lambda = sin(lambda)
cos_lambda = cos(lambda)
sin_sigma = sqrt((cos_u2 * sin_lambda) * (cos_u2*sin_lambda) +
(cos_u1*sin_u2-sin_u1*cos_u2*cos_lambda) * (cos_u1*sin_u2-sin_u1*cos_u2*cos_lambda))
cos_sigma = sin_u1*sin_u2 + cos_u1*cos_u2*cos_lambda
sigma = atan2(sin_sigma, cos_sigma)
alpha = asin(cos_u1 * cos_u2 * sin_lambda / sin_sigma)
cos_sq_alpha = cos(alpha) * cos(alpha)
cos2sigma_m = cos_sigma - 2*sin_u1*sin_u2/cos_sq_alpha
cc = f/16*cos_sq_alpha*(4+f*(4-3*cos_sq_alpha))
lambda_pi = lambda
lambda = L + (1-cc) * f * sin(alpha) *
(sigma + cc*sin_sigma*(cos2sigma_m+cc*cos_sigma*(-1+2*cos2sigma_m*cos2sigma_m)))
}
usq = cos_sq_alpha*(a*a-b*b)/(b*b);
aa = 1 + usq/16384*(4096+usq*(-768+usq*(320-175*usq)))
bb = usq/1024 * (256+usq*(-128+usq*(74-47*usq)))
delta_sigma = bb*sin_sigma*(cos2sigma_m+bb/4*(cos_sigma*(-1+2*cos2sigma_m*cos2sigma_m)-
bb/6*cos2sigma_m*(-3+4*sin_sigma*sin_sigma)*(-3+4*cos2sigma_m*cos2sigma_m)))
c = b*aa*(sigma-delta_sigma)