bombinans/fourdjs
1
1
Fork 0
Code Issues 9 Pull Requests Packages Projects Releases Wiki Activity

Still trying to get this working and understand why it maxes out at 81

Browse Source
This commit is contained in:
Mike Lynch 2025-12-06 15:11:32 +11:00
parent 1e59b55f5e
commit 0ae1d66669
1 changed files with 67 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

96
explore_120cell.js
View File

@ -100,11 +100,6 @@ export function chord_survey() {
}
}
// how to proceed: start with the 120-cell that has five 600-cells inscribed
// in it. Take the 120 nodes from one of those 600-cells, and construct a 5-cell
// from each such that all of the vertices are on different 600-cells.
// collect them and output by label because every 5-cell is on all 5 600-cells
function overlap(c1, c2) {
for( const l in c1 ) {
@ -116,13 +111,13 @@ function overlap(c1, c2) {
}
export function gather_5cells() {
const cell120 = POLYTOPES.cell120_inscribed();
export function gather_5cells(cell120) {
const CHORD5 = round_dist(Math.sqrt(2.5));
const bins = [];
const all = [];
cell120.nodes.filter((n) => n.label === 1).map((n) => {
const g = distance_group(cell120, n, CHORD5);
const cells = [ ];
const g = distance_group(cell120, n, CHORD5);
for( const pair of g ) {
let seen = false;
for( const cell of cells ) {
@ -146,26 +141,69 @@ export function gather_5cells() {
cells.push(cell);
}
}
//console.log(`From ${n.id}`);
//console.log(cells);
for( const cell of cells ) {
let binned = false;
for( const bin of bins ) {
const overlaps = bin.filter((b) => overlap(b, cell));
if( overlaps.length === 0 ) {
bin.push(cell);
binned = true;
break;
}
}
if( !binned ) {
console.log(`new bin for ${JSON.stringify(cell)}`);
bins.push([ cell ]);
}
}
//console.log(bins);
})
;
all.push(...cells);
});
return all;
}
gather_5cells();
function audit_5cells(cells) {
// this verifies that for each label (a 600-cell set), each of its
// vertices is in exactly 7 5-cells. It checks out.
['1','2','3','4','5'].map((l) => {
const sets = {};
for( const cell of cells ) {
const lv = cell[l];
if( !(lv in sets) ) {
sets[lv] = [];
}
sets[lv].push(cell);
}
for( const lv in sets ) {
const ok = ( sets[lv].length === 7 ) ? 'ok' : 'miss';
console.log(`${l},${lv},${sets[lv].length},${ok}`);
}
});
}
function try_120_5_cells(cell120, cells, l) {
// iterate over every vertex in the 600-cell defined by label l,
// get all 7 5-cells including that vertex, and add them if they are
// disjoint with what we already have
const vertices = cell120.nodes.filter((n) => n.label === l);
const cellset = [];
for( const v of vertices ) {
console.log(`Vertex ${v.id}`);
const vcells = cells.filter((c) => c[l] === v.id);
const overlap_any = (cs, c) => {
for( const seen of cs ) {
console.log(c);
if( overlap(seen, c) ) {
console.log("overlap");
console.log(seen);
console.log(c);
return true;
}
}
return false;
}
const disjoint = vcells.filter((c) => ! overlap_any(cellset, c));
console.log(`Found ${disjoint.length} disjoint cells`);
if( disjoint.length > 0 ) {
cellset.push(disjoint[0]);
}
}
console.log(`Found total of ${cellset.length} disjoint cells`);
//console.log(cellset);
}
const cell120 = POLYTOPES.cell120_inscribed();
const all5 = gather_5cells(cell120);
try_120_5_cells(cell120, all5, 1);