<gama-local> and <network>A pair tag <gama-local> contains a single pair tag <network>
that contains the network definition. The definition of the network is
composed of three sections:
<description> of the network (annotation or comments),
<parameters /> and
<points-observations> section.
The sections <description> and <parameters /> are
optional, the section <points-observations> is mandatory. These
three sections may be presented in any order and may be repeated several
times (in such a case, the corresponding sections are linked
together by the software).
The pair tag <network> has two optional attributes axes-xy
and angles. These attributes are used to describe orientation of
the xy orthogonal coordinate system axes and the orientation of the
observed angles and/or directions.
axes-xy="ne" orientation of axes x and y; value
ne implies that axis x is oriented north and axis y
is oriented east. Acceptable values are ne, sw,
es, wn for left-handed coordinate systems and en,
nw, se, ws for right-handed coordinate systems
(default value is ne).
angles="right-handed" defines counterclockwise observed angles
and/or directions, value left-handed defines clockwise observed
angles and/or directions (default value is left-handed).
Many geodetic systems are right handed with x axis oriented
east, y axis oriented north and counterclockwise angular
observations. Example of left-handed orthogonal system with different
axes orientation is coordinate system Krovak used in the Czech
Republic where the axes x and y are oriented south and
west respectively.
GNU Gama can adjust any combination of coordinate and angular systems.
<gama-local>
<network>
<description> ... </description>
<parameters ... />
<points-observations> ... </points-observations>
</network>
</gama-local>
It is planned in future versions of the program to allow more
<network> tags (analysis of deformations etc.) and definitions of
new tags.