FA-97754 / Knitting and sewing pattern grading / Member archive

Held-together yarn weight estimator: strand combination · case 04

Holding two strands together is classified as the same weight as one.

Member previewVariant 4 · 3 implementations · 8 checks per implementation

Case contract

Strands held together combine as 1/sqrt(sum(1/wpi^2)), rounded half-up to 0.1. Classify the rounded value: >=30 lace, >=18 fingering, >=14 dk, >=11 worsted, >=8 bulky, else super bulky. Empty -> "error: no strands". Return [wpi, class].

Why this case matters

Knitters hold yarns double to substitute a heavier weight and need the combined wraps per inch.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
two dk strands	`[14.0, "dk"]`	`[9.9, "bulky"]`	Failed

MEMBER ARCHIVE

The complete case is available to members.

This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

Member access is invitation-based. Sign in with your invited account to inspect the sources.