Bounding csv data to topojson path - cloropleth

Question

I am trying to bound some data to a topojson map. So far I've been able to draw the map of the US, with each path labeled by id: state name. What I'd like to do now is to bind data I have on an external csv to the map, to show each state of a hue based on the value in the csv (aka cloropleth). I've been looking for guides but I don't have the knowledge yet to understand the one on Mike Bostock's site, so I tried to bind the color with a function like so:

.attr("fill", "rgb(0, 0, " + Math.round(d.value * 255 / d3.max(d, function (d) {return d.value; })) + ")")

but it doesn't work. The page is here: http://www.dropbox.com/s/w2pe4omn895vt83/usa_malattie.html

Commenting out the last part, with the csv load, gives the map with the tooltip showing, that also disappear when loading the csv data. Any help on how to resolve this would be highly appreciated, thanks in advance!

EDIT: the csv looks like this:

id,value
"Kentucky",207.4
"Mississippi",200.5
"West Virginia",196.6
"Louisiana",196.4

the topojson like this:

{"type":"Topology","transform":{"scale":
0.011125945304891298,0.005248969801868182],
"translate":[-178.21759836236586,18.92178634508703]},
"objects":{"usa":{"type":"GeometryCollection",
"geometries":[{"type":"MultiPolygon","id":"Hawaii",
"arcs":[[[0]],[[1]],[[2]],[[3]],[[4]],[[5]],[[6]]],
"properties":{"STATE_NAME":"Hawaii"}},

link for the csv: http://dl.dropboxusercontent.com/u/37967455/usa_malattie/death_parse.csv link for the topojson: http://dl.dropboxusercontent.com/u/37967455/usa_malattie/usatopo.json

Could you post some simplified versions of your _topojson_ and _csv_ files? — Alex Filipovici, Aug 27 '13 at 15:28
See also : [How to add properties to topojson file?](http://stackoverflow.com/questions/18444261/) — Hugolpz, Aug 29 '13 at 05:36
yeah Alex Filipovici already suggested that solution! what I wanted to do was a bit different, but looks like merging is the best one — tomtomtom, Aug 29 '13 at 10:04

score 1 · Answer 1 · answered Aug 27 '13 at 16:43

1

You may try the following command:

topojson -o final.json -e death_parse.csv --id-property=id -p STATE_NAME,color=+value -- usatopo.json

answered Aug 27 '13 at 16:43

Alex Filipovici

31,789
6
54
78

yeah I thought of merging the files in one topojson, but I wanted to learn how to load the csv, so it could be possible to have the same map and load different csvs if needed – tomtomtom Aug 27 '13 at 16:55

Bounding csv data to topojson path - cloropleth

1 Answers1

Linked