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Topic: Date bands for Atlas grade mapping service please

The Atlas grade mapping service has parameters for start year, end year, border colour and fill colour to define the symbols that are mapped, but this only allows for one date band. As far as I can see, the only web service that allows multiple date bands is the Easy Map service - which allows three date bands to be defined, each with a fill and border colour for the symbols. Unfortunately I cannot use this service because my application does not allow iframes. I need the results to be an image that can be referenced via an <img src=...> HTML entry.

I don't know of an atlas that does not use at least two date classes (e.g. open and closed symbols to represent records before and after some cut date), and three is more typical these days. So could we please have the EasyMap style date band parameters available for Atlas grade maps?

By the way, the documentation page for the Atlas web service (data.nbn.org.uk/Documentation/Web_Services/Atlas_Grade_Maps/) has a link to further information about date filtering about half way down the page - but it is broken (produces a 404 error).

2 (edited by matt.debont 12-08-2014 15:18:37)

Re: Date bands for Atlas grade mapping service please

Hi Stuart, a quick response here as its useful for everyone in this case, there is an undocumented feature for the Web Mapping Services we are using (documentation is here https://data.nbn.org.uk/Documentation/W … _Services/ ).

You can see an example on the Grid_Map pages of banding, this is essentially what powers the easy map service itself so you can use the same thing to produce a map for a single species with date banding

Use the band=startYear-endYear,hexcolour parameter in a normal request to the WMS so you can end up with something like this for three bands (I don't think there is a limit technically)

&band=1600-1990,ffff00,000000&band=1990-2000,ff7f00,000000&band=2001-2014,ff0000,000000

You would end up with something like this;
https://gis.nbn.org.uk/SingleSpecies/NB … 000,000000

I will try and get round to updating the documentation for the Single Species Map at some point to reflect this capability

Matt

Matt Debont
Application Developer
Joint Nature Conservation Committee, Monkstone House, City Road, Peterborough PE1 1JY, UK