Looking at the visualizations provide I don't see a visual proof that the code is able to extract city blocks; by city block, I mean as defined by Wikipedia here:
https://en.m.wikipedia.org/wiki/City_block
Proof might be an interactive map that shows the city block of a selected area in NYC.
Is there a visual proof in the walkthrough I'm not seeing?
You can also go to http://geojson.io and load the generated file for more interactivity (select, delete, add your own polygons, etc.) or open it in QGIS.
In the Results section I had a screenshot of the generated polygons in both QGIS and geojson.io (polygons are separated by thick black lines and their area is colored gray).
Reluctant to respond, since it's clear that bit of more effort went into your comment than mine.
Basically for me when I click the interactive map I get a response, which is a pinned blank text-box with a x to close it. Thing is that I'm unable see that a city block is highlighted via a click; the text box simple appears where I click, unless it's outside the targeted area; for example, in the river.
Looking at the raw JSON it does appear the block are extracted.
So, putting aside "seeing" it, appears you're confirming it extracts single blocks as objects and isn't doing something else like if two blocks are attached, they're not sharing the path that's between them.
Proof might be an interactive map that shows the city block of a selected area in NYC.
Is there a visual proof in the walkthrough I'm not seeing?