Slope distances (space distances) are written using an empty-element tag
<s-distance /> with attributes
from = "..." standpoint identification (optional)
to = "..." target identification
val = "..." observed slope distance
stdev = "..." standard deviation of observed slope distance
(optional)
from_dh = "..." instrument height (optional)
to_dh = "..." reflector/target height (optional)
Similar to horizontal distances, one observation set may group slope distances observed from several standpoints.
<s-distance from = "2" to = "1" val = "658.824" />
<s-distance to ="422" val="648.618" stdev="5.0" />
<s-distance to ="408" val="482.578" />