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Topic: Bug in NBN distribution maps?

The attached file (original bug) shows the distribution map for Quercus cerris. I'm using the grid map page - https://data.nbn.org.uk/Taxa/NBNSYS0000003843/Grid_Map

I've set the date ranges (from the top) to 1600 to 1990 (red), then 1991 to 2017 (ornage); finally I added a base layer of 1600 to 1990 (yellow) to show the full data.

My expectation was that all the records would be picked up by one of the first two searches so the map would show no yellow, but this is clearly not the case.

(more follows)

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Re: Bug in NBN distribution maps?

Obvious assumption: that the upper or lower year in the range is not being included (perhaps the searches use 1st Jan rather than actually looking at the year)

So I changed the date ranges to overlap: 1600-1990 and 1989-2017. The map still shows yellow.

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Re: Bug in NBN distribution maps?

I can't get files to upload.

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4 (edited by charliebarnes 06-03-2017 11:31:58)

Re: Bug in NBN distribution maps?

I'm guessing but the record at NK05 has a date range of 1987 - 1999. It appears the map is checking both of these dates to see which bracket to put the record in.

Charlie Barnes
Information Officer
Greater Lincolnshire Nature Partnership

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Re: Bug in NBN distribution maps?

I think I've worked it out: the Norfolk data only appears if you select a date range that includes 1988-1999. Presumably this was a batch of data with a start date in 1988 and an end date in 1999 (or in 1988 if the search uses 1st Jan rather than being a true year search)

So it's down to how date ranges are handled.