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 1 dwg/objects-write.js:818 CadCraft, BimCraft, ModelCraft, TakeoffCraft, CivilCraft
```
const rational = ctl.some((p) => p.w !== undefined && p.w !== 1);
```
!== in p.w !== 1. Fine for a value that is set, not computed (a default scale). If it comes from a calculation, use an epsilon. Reviewed: DWG object values written and read.
Against 1 dwg/table-write.js:70 in insertScale CadCraft, ModelCraft, CivilCraft, DetailCraft, PartCraft
```
if (sx === 1 && sy === 1 && sz === 1) w.BB(3);
```
=== in sx === 1. Fine for a value that is set, not computed (a default scale). If it comes from a calculation, use an epsilon. Not in the register.
Against 1 dwg/table-write.js:70 in insertScale CadCraft, ModelCraft, CivilCraft, DetailCraft, PartCraft
```
if (sx === 1 && sy === 1 && sz === 1) w.BB(3);
```
=== in sy === 1. Fine for a value that is set, not computed (a default scale). If it comes from a calculation, use an epsilon. Not in the register.
Against 1 dwg/table-write.js:70 in insertScale CadCraft, ModelCraft, CivilCraft, DetailCraft, PartCraft
```
if (sx === 1 && sy === 1 && sz === 1) w.BB(3);
```
=== in sz === 1. Fine for a value that is set, not computed (a default scale). If it comes from a calculation, use an epsilon. Not in the register.
Against 1 dwg/table-write.js:72 in insertScale CadCraft, ModelCraft, CivilCraft, DetailCraft, PartCraft
```
else if (sx === 1) { w.BB(1); w.DD(sy, 1); w.DD(sz, 1); }
```
=== in sx === 1. Fine for a value that is set, not computed (a default scale). If it comes from a calculation, use an epsilon. Not in the register.
Against 1 dxf-model.js:58 in msg CadCraft, BimCraft, TakeoffCraft, CivilCraft
```
if (typeof s === 'object') s = s['=' + fills.n] ?? (Number(fills.n) === 1 ? s.one : s.other) ?? s.other;
```
=== in Number(fills.n) === 1. Fine for a value that is set, not computed (a default scale). If it comes from a calculation, use an epsilon. Reviewed: DXF reading into the shared drawing model.
Against 1 live-crypto.js:329 in verifyAssertion CadCraft, BimCraft, ModelCraft, MarkupCraft, TakeoffCraft, CivilCraft, DetailCraft, PartCraft
```
if (!sig || !claims || claims.v !== 1 || typeof claims.name !== 'string') return { ok: false, reason: 'format' };
```
!== in claims.v !== 1. Fine for a value that is set, not computed (a default scale). If it comes from a calculation, use an epsilon. Not in the register.
Against 1 usd/usda-write.js:40 in subLayersText CadCraft, BimCraft, ModelCraft, TakeoffCraft, CivilCraft, DetailCraft, PartCraft
```
return asset(a) + (o && (o.offset !== 0 || o.scale !== 1) ? ' (' + layerOffsetText(o) + ')' : '');
```
!== in o.scale !== 1. Fine for a value that is set, not computed (a default scale). If it comes from a calculation, use an epsilon. Reviewed: Number text in USD files.
Against 1 usd/usda-write.js:47 in layerOffsetText CadCraft, BimCraft, ModelCraft, TakeoffCraft, CivilCraft, DetailCraft, PartCraft
```
if (o.scale !== 1) parts.push('scale = ' + num(o.scale, 'f64'));
```
!== in o.scale !== 1. Fine for a value that is set, not computed (a default scale). If it comes from a calculation, use an epsilon. Reviewed: Number text in USD files.
Against 1 usd/usda-write.js:172 in listItemText CadCraft, BimCraft, ModelCraft, TakeoffCraft, CivilCraft, DetailCraft, PartCraft
```
if (o && (o.offset !== 0 || o.scale !== 1)) parts.push(layerOffsetText(o));
```
!== in o.scale !== 1. Fine for a value that is set, not computed (a default scale). If it comes from a calculation, use an epsilon. Reviewed: Number text in USD files.
Against 1 clip.js:49 in readClip CivilCraft
```
if (!obj || typeof obj !== 'object' || obj.format !== CLIP_FORMAT || obj.v !== 1 || !Array.isArray(obj.pts)) return null;
```
!== in obj.v !== 1. Fine for a value that is set, not computed (a default scale). If it comes from a calculation, use an epsilon. Not in the register.
Against 0 ifc/geo-tri.js:133 in clip BimCraft, TakeoffCraft, CivilCraft, DetailCraft
```
if (cross(a, e, c) === 0 && !between(a, e, c)) { remove(e); count--; if (e === stop) stop = c; e = c; if (count < 3) return; continue; }
```
=== in cross(a, e, c) === 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 by ear clipping.
Against 0 ifc/geo-tri.js:145 in clip BimCraft, TakeoffCraft, CivilCraft, DetailCraft
```
while (p.next !== e) { if (cross(e, p, p.next) !== 0) out.push(e.i, p.i, p.next.i); p = p.next; }
```
!== in cross(e, 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 by ear clipping.
Against 0 raster.js:118 in openGeoTiff BimCraft, CivilCraft
```
const scale = Number.isFinite(meta.scale) && meta.scale !== 0 ? meta.scale : 1;
```
!== in meta.scale !== 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Elevation grids read from GeoTIFF and ASCII files.
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 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.
Against 0 featureline.js:228 in offsetFeature CivilCraft
```
if (!fin(dist) || dist === 0) return { f: null, problem: t('fl.offset.zero') };
```
=== in dist === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: Feature line grades, arcs, offsets and crossings, Feature line arcs as straight pieces.
Against 0 gis-cad-ui.js:171 in surveyRun CivilCraft
```
const fromBlocks = chosenRefs().map((x) => ({ x: x.x, y: x.y, z: Number.isFinite(x.z) && x.z !== 0 ? x.z : null }));
```
!== in x.z !== 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 gis-cad-ui.js:207 in howChoices CivilCraft
```
const flat = chosenRefs().every((x) => x.z === 0);
```
=== in x.z === 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 landxml.js:448 in inf CivilCraft
```
const inf = (v) => String(v).trim().toUpperCase() === 'INF' || !Number.isFinite(Number(v)) || Number(v) === 0;
```
=== in Number(v) === 0. Usually fine as a guard against dividing by zero; check it is not meant to catch a near-zero value too. Reviewed: LandXML export and import.