Resources Numerical accuracy

Equality comparisons

Where the code asks whether two decimal numbers are exactly equal. A floating-point result can differ from another in the last digit after a few transformations, so a mesh run through several of them can change the length of an edge, or miss a match. Compare with < or > where a range is meant, and with a documented epsilon where equality is.

316 comparisons to look at
149 files
175 likely to matter (against a decimal, or two computed values)
Scanned November 6, 2026

These are places worth checking, not confirmed bugs. The scan reads how the code is written, not what it is meant to do, so some entries are fine as they are: a test against exactly 0 is often a deliberate guard against dividing by zero. It skips text, counts and indexes, and any comparison it cannot be sure involves decimal numbers, so there are likely more in the code than are listed here.

Against 0 addons/trusscraft/lib/design.js:130 in designTruss CadCraft, BimCraft, ModelCraft, PartCraft
```
const closed = g.profile ? g.nodes.find((n) => n.x === 0 && n.z === 0) : true;
```
=== in n.x === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Truss member forces and timber checks.
Against 0 addons/trusscraft/lib/design.js:130 in designTruss CadCraft, BimCraft, ModelCraft, PartCraft
```
const closed = g.profile ? g.nodes.find((n) => n.x === 0 && n.z === 0) : true;
```
=== in n.z === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Truss member forces and timber checks.
Against 0 lencalc.js:130 in term CadCraft, ModelCraft, MarkupCraft, TakeoffCraft, CivilCraft, DetailCraft
```
if (o.t === '/' && b.v === 0) throw new CalcError('divide', o.pos);
```
=== in b.v === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Arithmetic on typed lengths.
Against 0 lisp/dxflist.js:152 in fromPairs CadCraft
```
else if (has(62)) { const c = get(pairs, 62); e.color = c === 256 ? null : Math.abs(c) === 0 ? 0 : Math.min(255, Math.abs(c)); }
```
=== in Math.abs(c) === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Drawing values handed to and from LISP routines.
Against 0 m3d/earcut.js:51 in filterPoints CadCraft, TakeoffCraft
```
if (!p.steiner && (equals(p, p.next) || area(p.prev, p, p.next) === 0)) {
```
=== in area(p.prev, p, p.next) === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Triangulation of faces with holes.
Against 0 m3d/lencalc.js:130 in term CadCraft
```
if (o.t === '/' && b.v === 0) throw new CalcError('divide', o.pos);
```
=== in b.v === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Not in the register.
Against 0 m3d/tools.js:727 in value CadCraft
```
if (!Number.isFinite(deg) || deg === 0) return false;
```
=== in deg === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: 3D drawing and editing tools.
Against 0 m3d/tools.js:1138 in pickPoint CadCraft
```
this.k = 1 / Math.max(len(this.T.localDir(this.n)), 1e-9) === 0 ? 1 : len(this.T.localDir(this.n));
```
=== in 1 / Math.max(len(this.T.localDir(this.n)), 1e-9) === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: 3D drawing and editing tools.
Against 0 pointcloud.js:721 in scanPtx CadCraft, BimCraft
```
if (px === 0 && py === 0 && pz === 0) { missing++; return; }
```
=== in px === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Point cloud positions and read-in values.
Against 0 pointcloud.js:721 in scanPtx CadCraft, BimCraft
```
if (px === 0 && py === 0 && pz === 0) { missing++; return; }
```
=== in py === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Point cloud positions and read-in values.
Against 0 pointcloud.js:721 in scanPtx CadCraft, BimCraft
```
if (px === 0 && py === 0 && pz === 0) { missing++; return; }
```
=== in pz === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Point cloud positions and read-in values.
Against 0 process/env/cheminfo.js:182 in groupsOf CadCraft, BimCraft
```
if (arom) inc(a.h === 1 ? 'ring =CH-' : a.h === 0 ? 'ring =C<' : 'ring =CH-');
```
=== in a.h === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Molar mass and group-contribution estimates.
Against 0 process/env/cheminfo.js:189 in groupsOf CadCraft, BimCraft
```
else if (a.h === 0 && nb[i].length === 2 && !inRing[i] && nb[i].every((x) => x.order === 1 && !mol.atoms[x.o].aromatic)) inc('-O- (non-ring)');
```
=== in a.h === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Molar mass and group-contribution estimates.
Against 0 process/equip/pipestress.js:109 in buildModel CadCraft, BimCraft
```
const W = { id: 'W', name: 'Weight', kind: 'dead', selfWeight: 1, loads: fm.members.map((e) => ({ type: 'udl', member: e.id, dir: 'Z', w: -(wContents + wIns) })).filter((l) => l.w !== 0) };
```
!== in l.w !== 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Pipe stress checks.
Against 0 usd/earcut.js:52 in filterPoints CadCraft, BimCraft, ModelCraft, TakeoffCraft, CivilCraft, DetailCraft, PartCraft
```
if (!p.steiner && (equals(p, p.next) || area(p.prev, p, p.next) === 0)) {
```
=== in area(p.prev, p, p.next) === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Polygon triangulation (ear clipping).
Against 0 usd/usda-read.js:476 in component CadCraft, BimCraft, ModelCraft, TakeoffCraft, CivilCraft, DetailCraft, PartCraft
```
if (c.k === 'num') { this.i++; return c.v !== 0; }
```
!== in c.v !== 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Floats read from USD files.
Against 0 wheel-pad.js:20 in isSwipe CadCraft, BimCraft, MarkupCraft, TakeoffCraft, CivilCraft
```
const step = dx === 0 && ((Number.isFinite(e.wheelDeltaY) && e.wheelDeltaY !== 0 && e.wheelDeltaY % 120 === 0) || (Number.isInteger(dy) && Math.abs(dy) >= 50));
```
=== in dx === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Not in the register.
Against 0 wheel-pad.js:22 in isSwipe CadCraft, BimCraft, MarkupCraft, TakeoffCraft, CivilCraft
```
if (dx !== 0 || !Number.isInteger(dy) || Math.abs(dy) < 50) { this.until = t + 400; return true; }
```
!== in dx !== 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Not in the register.