struct to learn from https://observablehq.com/@d3/disjoint-force-directed-graph by bostock

spokes_and_lcs.json

{
 "nodes": [
{"group": "Topic", "id": "Climate Change and Sustainability", "radius": 15}, 
{"group": "Topic", "id": "Conservation", "radius": 3}, 
{"group": "Topic", "id": "Environmental Communications", "radius": 6}, 
{"group": "Topic", "id": "Environmental Policy, Policy Analysis, and Economics"}, 
{"group": "Topic", "id": "Forest Ecology and Management", "radius": 10}, 
{"group": "Topic", "id": "Urban Science and Practice", "radius": 6}, 
{"group":"Spoke", "id":"Center for Business and the Environment at Yale"},
{"group":"Spoke", "id":"Global Institute of Sustainable Forestry"},
{"group":"Spoke", "id":"Hixon Center for Urban Ecology"},
{"group":"Spoke", "id":"SEARCH Center"},
{"group":"Spoke", "id":"The School Forests"},
{"group":"Spoke", "id":"Tropical Resources Institute"},
{"group":"Spoke", "id":"Yale Center for Environmental Communication"},
{"group":"Spoke", "id":"Yale Center for Environmental Law and Policy"},
{"group":"Spoke", "id":"Yale Green Chemistry & Green Engineering"},
{"group":"Spoke", "id":"Yale Program on Climate Change Communication"},
{"group":"Spoke", "id":"F&ES Climate Initiative"},
{"group":"Spoke", "id":"F&ES Sustainability Initiative"},
{"group":"Spoke", "id":"Quiet Corner Initiative"},
{"group":"Spoke", "id":"Ucross High Plains Stewardship Initiative"},
{"group":"Spoke", "id":"Urban Resources Initiative"},
{"group":"Spoke", "id":"Urban@Yale Initiative"},
{"group":"Learning Community", "id":"Business and the Environment"},
{"group":"Learning Community", "id":"Climate Change Science and Solutions"},
{"group":"Learning Community", "id":"Ecosystems, Conservation, and Land Management"},
{"group":"Learning Community", "id":"Energy and the Environment"},
{"group":"Learning Community", "id":"Environmental Policy Analysis"},
{"group":"Learning Community", "id":"Industrial Ecology and Green Engineering"},
{"group":"Learning Community", "id":"Nature and Society"},
{"group":"Learning Community", "id":"Water Resource Science and Management"},
{"group":"Spoke", "id":"The Forests Dialogue"},
{"group":"Spoke", "id":"Yale Forest Forum"},
{"group":"Spoke", "id":"Environmental Leadership and Training Institute"},
{"group":"Spoke", "id":"Sustaining Family Forests Initiative"},
{"group":"Spoke", "id":"Yale Climate Connections"}
],
"links": [
{"source": "Climate Change and Sustainability", "target": "Business and the Environment"},
{"source": "Climate Change and Sustainability", "target": "Center for Business and the Environment at Yale"},
{"source": "Climate Change and Sustainability", "target": "Climate Change Science and Solutions"},
{"source": "Climate Change and Sustainability", "target": "Climate Change Science and Solutions"},
{"source": "Climate Change and Sustainability", "target": "Energy and the Environment"},
{"source": "Climate Change and Sustainability", "target": "Energy and the Environment"},
{"source": "Climate Change and Sustainability", "target": "Environmental Policy Analysis"},
{"source": "Climate Change and Sustainability", "target": "F&ES Climate Initiative"},
{"source": "Climate Change and Sustainability", "target": "F&ES Sustainability Initiative"},
{"source": "Climate Change and Sustainability", "target": "Industrial Ecology and Green Engineering"},
{"source": "Climate Change and Sustainability", "target": "SEARCH Center"},
{"source": "Climate Change and Sustainability", "target": "Yale Center for Environmental Law and Policy"},
{"source": "Climate Change and Sustainability", "target": "Yale Climate Connections"},
{"source": "Climate Change and Sustainability", "target": "Yale Green Chemistry & Green Engineering"},
{"source": "Climate Change and Sustainability", "target": "Yale Program on Climate Change Communication"},
{"source": "Conservation", "target": "Ecosystems, Conservation, and Land Management"},
{"source": "Conservation", "target": "Ucross High Plains Stewardship Initiative"},
{"source": "Conservation", "target": "Water Resource Science and Management"},
{"source": "Environmental Communications", "target": "Climate Change Science and Solutions"},
{"source": "Environmental Communications", "target": "Environmental Policy Analysis"},
{"source": "Environmental Communications", "target": "Nature and Society"},
{"source": "Environmental Communications", "target": "Yale Center for Environmental Communication"},
{"source": "Environmental Communications", "target": "Yale Climate Connections"},
{"source": "Environmental Communications", "target": "Yale Program on Climate Change Communication"},
{"source": "Forest Ecology and Management", "target": "Ecosystems, Conservation, and Land Management"},
{"source": "Forest Ecology and Management", "target": "Environmental Leadership and Training Institute"},
{"source": "Forest Ecology and Management", "target": "Global Institute of Sustainable Forestry"},
{"source": "Forest Ecology and Management", "target": "Nature and Society"},
{"source": "Forest Ecology and Management", "target": "Quiet Corner Initiative"},
{"source": "Forest Ecology and Management", "target": "Sustaining Family Forests Initiative"},
{"source": "Forest Ecology and Management", "target": "The Forests Dialogue"},
{"source": "Forest Ecology and Management", "target": "The School Forests"},
{"source": "Forest Ecology and Management", "target": "Tropical Resources Institute"},
{"source": "Forest Ecology and Management", "target": "Yale Forest Forum"},
{"source": "Urban Science and Practice", "target": "Climate Change Science and Solutions"},
{"source": "Urban Science and Practice", "target": "Hixon Center for Urban Ecology"},
{"source": "Urban Science and Practice", "target": "Nature and Society"},
{"source": "Urban Science and Practice", "target": "Urban Resources Initiative"},
{"source": "Urban Science and Practice", "target": "Urban@Yale Initiative"},
{"source": "Urban Science and Practice", "target": "Water Resource Science and Management"}
]}

struct.json

{
 "nodes": [
{"group": "Topic", "id": "Climate Change and Sustainability", "radius": 15}, 
{"group": "Topic", "id": "Conservation", "radius": 3}, 
{"group": "Topic", "id": "Environmental Communications", "radius": 6}, 
{"group": "Topic", "id": "Environmental Policy, Policy Analysis, and Economics"}, 
{"group": "Topic", "id": "Forest Ecology and Management", "radius": 10}, 
{"group": "Topic", "id": "Urban Science and Practice", "radius": 6}, 
{"group":"Center", "id":"Center for Business and the Environment at Yale"},
{"group":"Center", "id":"Global Institute of Sustainable Forestry"},
{"group":"Center", "id":"Hixon Center for Urban Ecology"},
{"group":"Center", "id":"SEARCH Center"},
{"group":"Center", "id":"The School Forests"},
{"group":"Center", "id":"Tropical Resources Institute"},
{"group":"Center", "id":"Yale Center for Environmental Communication"},
{"group":"Center", "id":"Yale Center for Environmental Law and Policy"},
{"group":"Center", "id":"Yale Green Chemistry & Green Engineering"},
{"group":"Center", "id":"Yale Program on Climate Change Communication"},
{"group":"Initiative", "id":"F&ES Climate Initiative"},
{"group":"Initiative", "id":"F&ES Sustainability Initiative"},
{"group":"Initiative", "id":"Quiet Corner Initiative"},
{"group":"Initiative", "id":"Ucross High Plains Stewardship Initiative"},
{"group":"Initiative", "id":"Urban Resources Initiative"},
{"group":"Initiative", "id":"Urban@Yale Initiative"},
{"group":"Learning Community", "id":"Business and the Environment"},
{"group":"Learning Community", "id":"Climate Change Science and Solutions"},
{"group":"Learning Community", "id":"Ecosystems, Conservation, and Land Management"},
{"group":"Learning Community", "id":"Energy and the Environment"},
{"group":"Learning Community", "id":"Environmental Policy Analysis"},
{"group":"Learning Community", "id":"Industrial Ecology and Green Engineering"},
{"group":"Learning Community", "id":"Nature and Society"},
{"group":"Learning Community", "id":"Water Resource Science and Management"},
{"group":"Program", "id":"The Forests Dialogue"},
{"group":"Program", "id":"Yale Forest Forum"},
{"group":"Project", "id":"Environmental Leadership and Training Institute"},
{"group":"Project", "id":"Sustaining Family Forests Initiative"},
{"group":"Project", "id":"Yale Climate Connections"}
],
"links": [
{"source": "Climate Change and Sustainability", "target": "Business and the Environment"},
{"source": "Climate Change and Sustainability", "target": "Center for Business and the Environment at Yale"},
{"source": "Climate Change and Sustainability", "target": "Climate Change Science and Solutions"},
{"source": "Climate Change and Sustainability", "target": "Climate Change Science and Solutions"},
{"source": "Climate Change and Sustainability", "target": "Energy and the Environment"},
{"source": "Climate Change and Sustainability", "target": "Energy and the Environment"},
{"source": "Climate Change and Sustainability", "target": "Environmental Policy Analysis"},
{"source": "Climate Change and Sustainability", "target": "F&ES Climate Initiative"},
{"source": "Climate Change and Sustainability", "target": "F&ES Sustainability Initiative"},
{"source": "Climate Change and Sustainability", "target": "Industrial Ecology and Green Engineering"},
{"source": "Climate Change and Sustainability", "target": "SEARCH Center"},
{"source": "Climate Change and Sustainability", "target": "Yale Center for Environmental Law and Policy"},
{"source": "Climate Change and Sustainability", "target": "Yale Climate Connections"},
{"source": "Climate Change and Sustainability", "target": "Yale Green Chemistry & Green Engineering"},
{"source": "Climate Change and Sustainability", "target": "Yale Program on Climate Change Communication"},
{"source": "Conservation", "target": "Ecosystems, Conservation, and Land Management"},
{"source": "Conservation", "target": "Ucross High Plains Stewardship Initiative"},
{"source": "Conservation", "target": "Water Resource Science and Management"},
{"source": "Environmental Communications", "target": "Climate Change Science and Solutions"},
{"source": "Environmental Communications", "target": "Environmental Policy Analysis"},
{"source": "Environmental Communications", "target": "Nature and Society"},
{"source": "Environmental Communications", "target": "Yale Center for Environmental Communication"},
{"source": "Environmental Communications", "target": "Yale Climate Connections"},
{"source": "Environmental Communications", "target": "Yale Program on Climate Change Communication"},
{"source": "Forest Ecology and Management", "target": "Ecosystems, Conservation, and Land Management"},
{"source": "Forest Ecology and Management", "target": "Environmental Leadership and Training Institute"},
{"source": "Forest Ecology and Management", "target": "Global Institute of Sustainable Forestry"},
{"source": "Forest Ecology and Management", "target": "Nature and Society"},
{"source": "Forest Ecology and Management", "target": "Quiet Corner Initiative"},
{"source": "Forest Ecology and Management", "target": "Sustaining Family Forests Initiative"},
{"source": "Forest Ecology and Management", "target": "The Forests Dialogue"},
{"source": "Forest Ecology and Management", "target": "The School Forests"},
{"source": "Forest Ecology and Management", "target": "Tropical Resources Institute"},
{"source": "Forest Ecology and Management", "target": "Yale Forest Forum"},
{"source": "Urban Science and Practice", "target": "Climate Change Science and Solutions"},
{"source": "Urban Science and Practice", "target": "Hixon Center for Urban Ecology"},
{"source": "Urban Science and Practice", "target": "Nature and Society"},
{"source": "Urban Science and Practice", "target": "Urban Resources Initiative"},
{"source": "Urban Science and Practice", "target": "Urban@Yale Initiative"},
{"source": "Urban Science and Practice", "target": "Water Resource Science and Management"}
]}