Green Map Meeting
Every Thursday, 18:30
Electron Club, CCA, Glasgow

green map data collection

Posted by hclinch Wednesday, 15 August 2007- 8:44 pm
This is all from memory, so it's a little spotty. I'll open my database later.
I kept things minimal, with a separate layer per type of (related) feature(s):

Symbol(The actual character for the thingy in the green map font)
Notes (Street Address, Phone Number, URL; these could be individual fields)

Symbol allows you to conflate several related things (e.g; farmer's markets
and vegetarian restaurants) into a single layer for ease of managment. Also,
if you're not uber picky about symbol placement, or are working with a large
format output, leveraging the labeling features of your GIS package (esp.
ArcGIS + Maplex) can greatly reduce the amount of effort required to manually
cope with clutter.

Weight is *very* helpful, and sense "B" is unfortunately absent in most
greenmaps. I used this in three ways A) I am able to gather data on all
varieties of things with respect to the topic, regardless of importance, and
later filter them out from presentation as I see fit B) vary the size of the
symbol in proportion to its importance, thereby allowing for denser display
of information with less clutter (on the Cambridge Green Map the Zipcars,
community gardens, and subway symbols are all scaled) C) the city provided
data, in a rather natural manner, conflates no bicycle riding on sidewalk
zones with the bicyle lane geometry. I applied a negative weight to these
features to more clearly set them off in my own databse, while allowing for
easy integration of future data revisions by the city.

Verified is used in a similar way to the first sense of weight, anything I'm
informed of, or suspect might be relevant gets added. But final layout only
displays those things which I have been able to verify are present and correct.

Something I probably should have included was a field indicating the source
of the data. Yes, you can use FGDC metadata for this, but it's a PITA and
suboptimal in this case. For many themes I merged a handful of features from
several random datasets. More than once I had to go back and figure out where
this park or that pond came from.
Free map of local environmental resources:
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