#Notes re A Quick CartoDB Intro
more to follow
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create an account.
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create new map
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click on add data (looks as if it's upload, but you can also post the url to csv, geojson etc).
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Use this url: https://github.com/sfsheath/roman-amphitheaters/blob/master/roman-amphitheaters.geojson (Thanks to Sebastian Heath for making this data available!)
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then, on left hand side, look for 'base map'. Click the 'plus' sign by 'Yours'.
We're going to get the URL for a historical map. In the pop up, it says 'xyz'. This means it's looking for a tiles-based URL (like what google maps serves up).
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Go to this: http://warp.worldmap.harvard.edu/maps/2273
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It's a georectifyied map of the Roman empire. Click on 'Export'.
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Click on 'tiles base url'. The map will appear in your browser. You want the URL, which will be: http://warp.worldmap.harvard.edu/maps/tile/2273/z/x/y.png
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You'll need to modify this URL like so:
http://warp.worldmap.harvard.edu/maps/tile/2273/{z}/{x}/{y}.png
(If you grabbed a map from the NYPL mapwarper service, those curley brackets would already be there. This is a peculiarity of the Harvard version of mapwarper that those curley brackets are missing. The thing is, the Harvard service will let you upload a map to georectify, whereas the NYPL version only includes maps already in their collection to be rectified).
- Copy your modified URL, go back to the CartoDB window, and paste that URL in the box for 'XYZ'. Click 'add basemap'.
You now have a map with a historical basemap and real data on top! On the right hand side of the screen, you can use various 'wizards' to style the data you've got. See what you can come up with. Share your map, add its URL to your open notebook.