Average depth and sac calculations

[Anton Lundin]

I have bin playing around with doing local sac calculations, and when i
found the ruler to measure things with it kinda verified my previous
findings.

If i take a look at the dives found in dives/sac-test.xml the average
depth the ruler prints and the average depth found in the stats tab
doesn't match up.

Eg. SAC test dive 5 shows average depth of 10m in the stats tab but it
shows average depth of 12.7 if you let the ruler calculate the average
depth for the whole dive.

This indicates why the sac in the statistics tab and the sac showed in
the patches i previously posted here doesn't match up.

It looks like the stats tab uses the mean-depth found from the dc but
the ruler uses the mean-depth calculated from the profile.

Both can't be right =)

//Anton

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Anton Lundin	+46702-161604