Interactive Extended Elevations

[Olly Betts]

In message <396108BD.4D0D6490@uts.edu.au>, Michael Lake writes:
>> >1 2  4.51  217 +05
>> >1 2  4.49  216 +04
>> >1 2  4.50  218 +05

>I presume that there can't be three 1->2 legs all different
>as above?

Ah, but there can - for example, imagine the case where people are unclear
of the correct tie-in point so survey to a couple of likely stations.  You
can easily get several versions of the same leg, and reality being what it
is the numbers are likely to vary.

Or from a statistical point of view what you have here is several samples
for the same leg.  In fact conceptually it might be better to think of them
as one leg with several measurements.  For this reason, I don't think (for
extended elevation purposes) that it's useful to break such legs
individually, so it isn't a real problem.

>> >Could you send me a brief explanation of what a node colouring algorithm
>> >is? I'm guessing that it probably doesn't actually have much to do with
>> >red,green, blue stuff.
>
>> Give each station a flag and set all these flags to false.

><STN name="2a" extendedElevReverse="0"/>

I'm talking of an algorithm here.  The flag would just be a member of an
object or structure (unless the program is using XML for internal data
structures, but that seems unlikely).

>For colouring you set that up in a XSL (extensible style
>language) style sheet which I have not yet got around to
>understanding. 

Ah, the colouring here isn't literal.  It's just a common way to talk about
this class of algorithm - perhaps better to think "node marking" instead of
"node colouring".

Cheers,
Olly