2.13 Zenith angles

Zenith angles are written using an empty-element tag <z-angle /> with the following attributes

• from = "..." standpoint identification (optional)
• to = "..." target identification
• val = "..." observed zenith angle; see Angular units
• stdev = "..." standard deviation of observed zenith angle (optional)
• from_dh = "..." instrument height (optional)
• to_dh = "..." reflector/target height (optional)

Similar to horizontal distances, one observation set may group zenith angles observed from several standpoints.

Example

     <z-angle from = "2"  to = "1" val = "79.6548" />
     <z-angle to ="422" val="85.4890"  stdev="5.0"  />
     <z-angle to ="408" val="95.7319" />