From 87f150f1d9e634f83cb8945abce2577a46bd7ed7 Mon Sep 17 00:00:00 2001 From: Frank Warmerdam Date: Fri, 14 Oct 2005 13:15:08 +0000 Subject: New git-svn-id: http://svn.osgeo.org/metacrs/proj/trunk@1305 4e78687f-474d-0410-85f9-8d5e500ac6b2 --- html/man_geod.html | 307 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 307 insertions(+) create mode 100644 html/man_geod.html (limited to 'html/man_geod.html') diff --git a/html/man_geod.html b/html/man_geod.html new file mode 100644 index 00000000..e9622c5c --- /dev/null +++ b/html/man_geod.html @@ -0,0 +1,307 @@ +Content-type: text/html + +Manpage of GEOD + +

GEOD

+Section: User Commands (1)
Updated: 2000/03/21 Rel. 4.4
Index +Return to Main Contents

+ + +

NAME

+ +geod - direct geodesic computations +
+ +invgeod - inverse geodesic computations + +

SYNOPSIS

+ +geod + ++ellps=<ellipse> + +[ +-afFIlptwW + +[ +args + +] ] [ ++args + +] +file[s] +
+ +invgeod + ++ellps=<ellipse> + +[ +-afFIlptwW + +[ +args + +] ] [ ++args + +] +file[s] + +

DESCRIPTION

+ +Geod + +(direct) and +invgeod + +(inverse) +perform geodesic (``Great Circle'') computations for determining +latitude, longitude and back azimuth of a terminus point +given a initial point latitude, longitude, azimuth and distance (direct) or +the forward and back azimuths and distance between an initial and +terminus point latitudes and longitudes (inverse). +

+ +The following runline control parameters can appear in any order: +

-I + +: +Specifies that the inverse geodesic computation is to be performed. +May be used with execution of +goed + +as an alternative to +invgeod + +execution. +
-a + +: +Latitude and longitudes of the initial and terminal points, +forward and back azimuths and distance are output. +
-ta + +: +A + +specifies a character employed as the first character to denote +a control line to be passed through without processing. +
-le + +: +Gives a listing of all the ellipsoids that may be selected with the ++ellps= + +option. +
-lu + +: +Gives a listing of all the units that may be selected with the ++units= + +option. +
-[f|F] format + +: +Format + +is a +printf + +format string to control the output form of the geographic coordinate values +(f) or distance value (F). +The default mode is DMS for geographic coordinates and "%.3f" for distance. +
-[w|W]n + +: +N + +is the number of significant fractional digits to employ for +seconds output (when the option is not specified, +-w3 + +is assumed). +When +-W + +is employed the fields will be constant width with leading zeroes. +
-p + +: +This option causes the azimuthal values to be output as unsigned +DMS numbers between 0 and 360 degrees. Also note -f. +

+ +The ++args + +run-line arguments are associated with geodetic parameters +for specifying the ellipsoidal or sphere to use. +See +proj + +documentation for full list of these parameters and contrl. +The options are processed in left to right order +from the run line. +Reentry of an option is ignored with the first occurance assumed to +be the desired value. +

+ +One or more +files + +(processed in left to right order) +specify the source of data to be transformed. +A - will specify the location of processing standard input. +If no files are specified, the input is assumed to be from +stdin. + +

+ +For direct determinations input data must be in latitude, +longitude, azimuth and distance order and output will be +latitude, longitude and back azimuth of the terminus point. +Latitude, longitude of the initial and terminus point are +input for the inverse mode and respective forward and back +azimuth from the initial and terminus points are output along +with the distance between the points. +

+ +Input geographic coordinates +(latitude and longitude) and azimuthal data must be in DMS format and input +distance data must be in units consistent with the ellipsoid +major axis or sphere radius units. +Output geographic coordinates will be in DMS +(if the +-f + +switch is not employed) to 0.001" +with trailing, zero-valued minute-second fields deleted. +Output distance data will be in the same units as the ellipsoid or +sphere radius. +

+ +The Earth's ellipsoidal figure may be selected in the same +manner as program +proj + +by using ++ellps=, +a=, +es=, + +etc. +

+ +Geod + +may also be used to determine intermediate points along either +a geodesic line between two points or along an arc of specified distance +from a geographic point. +In both cases an initial point must be specified with ++lat_1=lat + +and ++lon_1=lon + +parameters and either a terminus point ++lat_2=lat + +and ++lon_2=lon + +or a distance and azimuth from the initial point with ++S=distance + +and ++A=azimuth + +must be specified. +

+ +If points along a geodesic are to be determined then either ++n_S=integer + +specifying the number of intermediate points and/or ++del_S=distance + +specifying the incremental distance between points must be specified. +

+ +To determine points along an arc equidistant from the initial point both ++del_A=angle + +and ++n_A=integer + +must be specified which determine the respective angular increments +and number of points to be determined. + + +

EXAMPLE

+ +The following script determines the geodesic azimuths and distance in +U.S. stature miles from Boston, MA, to Portland, OR: +

: +
geod +ellps=clrk66 <<EOF -I +units=us-mi + 42d15'N 71d07'W 45d31'N 123d41'W + EOF +

+ +which gives the results: +

: +
-66d31'50.141" 75d39'13.083" 2587.504 +

+ +where the first two values are the +azimuth from Boston to Portland, the back azimuth from Portland to +Boston followed by the distance. + + +An example of forward geodesic use is to use the Boston location and determine +Portland's location by azimuth and distance: +

: + geod +ellps=clrk66 <<EOF +units=us-mi + 42d15'N 71d07'W -66d31'50.141" 2587.504 + EOF +

+ +which gives: +

: +
45d31'0.003"N 123d40'59.985"W 75d39'13.094" +

+ +Note: lack of precision in the distance value compromises +the precision of the Portland location. + +

HOME PAGE

+ +http://www.remotesensing.org/proj +

+ +

+This document was created by +man2html, +using the manual pages.
+Time: 13:14:56 GMT, October 14, 2005 + + -- cgit v1.2.3