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.TH LIBTELLURIAN_END_POINT 3 libtellurian
.SH NAME
libtellurian_end_point \- Calculate travel end-point
.SH SYNPOSIS
.nf
#include <libtellurian.h>
void libtellurian_end_point(double \fIlatitude1\fP, double \fIlongitude1\fP,
double \fIazimuth1\fP, double \fIdistance\fP,
double \fIlatitude2_out\fP, double \fIlongitude2_out\fP,
double *\fIazimuth2_out\fP);
void libtellurian_end_point_radians(double \fIlatitude1\fP, double \fIlongitude1\fP,
double \fIazimuth1\fP, double \fIdistance\fP,
double \fIlatitude2_out\fP, double \fIlongitude2_out\fP,
double *\fIazimuth2_out\fP);
.fi
.PP
Link with
.I -ltellurian
.IR -lm .
.SH DESCRIPTION
The
.BR libtellurian_end_point ()
function models the Earth as an oblate
spheroid and calculates a good approximate
location where a traveller starting at
.RI ( latitude1 ", " longitude1 )
travelling in an azimuthal direction,
.IR azimuth1 ,
for a specified
.IR distance ,
measured in meters, along the ellipsoid.
.PP
The location the traveller will end at will
be stored at
.RI ( *latitude2_out ", " *longitude2_out ).
along the ellipsoid. The azimuth from this
point to the starting point will be stored in
.IR *azimuth2_out .
.PP
However
.IR latitude2_out ,
.IR longitude2_out ,
and
.I azimuth2_out
can each, independently, be set to
.IR NULL ,
which will cause the function to skip the
specific calculations needed for the value
stored in the referenced memory.
.PP
The coordinates shall be specified, and are
returned, according to GPS and in degrees.
Likewise
.I azimuth1
shall be in degrees, and
.I *azimuth2_out
will be in degress.
.PP
The
.BR libtellurian_end_point_radians ()
function is identical to the
.BR libtellurian_end_point ()
function except that radians are
used instead of degress for
.IR latitude1 ,
.IR longitude1 ,
.IR azimuth1 ,
.IR *latitude2_out ,
.IR *longitude2_out ,
and
.IR *azimuth2_out .
.SH RETURN VALUE
None.
.SH ERRORS
None.
.SH SEE ALSO
.BR libtellurian (7)
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