Combining hills from two different bagging lists
Adding two lists together
As well as searching for hills based on their bagging type (specified by the “?list=” URL filter), a second hill type filter can be added (as “&list2=“) to give the total listing of two types of hill. This is the equivalent of adding the two lists together or the “union” of the two sets.
- For example if you wanted to list all Munros with all Munro Tops then you would use the URL filters like this …
Only hills in both lists
And if you use this in conjugation with display=onlyhillsinbothlists you can get the sub-set of hills which only belong to both lists (the intersection of the two sets).
- For example here are the Hewitts which are also Marilyns;
- or the “Marilyn Munros” i.e. the Munros which also have Marilyn status of 150m separation
Subtracting one list from another
Finally there is a new option of display=hillsnotinlist2 which gives you the sub-set of the hills from the main list but excluding those that are in list 2. The is equivalent of subtracting the 2nd list from the first.
- For example: Nuttalls that aren’t Hewitts
- or conversely Hewitts that aren’t Nuttalls
Read about more hill hill filters here…
or try them out in combination here…
Author: Phil Newby