Here's an example screenshot. The maximum gradient is showing as 3.4%, whereas the local gradient under my cursor is showing as 8.1%.
Where does the 3.4% figure come from?
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Here's an example screenshot. The maximum gradient is showing as 3.4%, whereas the local gradient under my cursor is showing as 8.1%.
Where does the 3.4% figure come from?
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Comments
Apologies - the screenshot lost resolution in the upload. You'll have to take my word for it :)
I think the best answer is that gradient calculation is remarkably complex and it’s something I’m still working on!
Fair enough! Thought it might have been a bug.
"It's complicated" is a completely valid answer.
Essentially the problem is that raw elevation data for a route is always pretty jagged. If you just total up all the ups and downs from the data, then the total climb ends up being about 50% more than it really is, and the gradients are equally off-whack. So we have to do a fair bit of smoothing, including disregarding the smallest ‘climbs’ which are actually just undulations on the flat… and that isn’t really working to my satisfaction yet. It’s on the list. :)