Elastic Insertion Stretch Limit Gap Tool

Description

Return relative extension, maximum-minus-required margin, and supplied-limit feasibility.

Ease, gathering and stretch compare lengths on a chosen baseline. Extra-length ratio, finished/flat ratio and extension from relaxed length are different conventions, so the denominator must be explicit.

Return relative extension, maximum-minus-required margin, and supplied-limit feasibility.

When to use this tool

Use Elastic Insertion Stretch Limit Gap when you need one stated ease, gauge or stretch relationship.

How to use the tool and how it works

Enter relaxedLength, insertionLength, maxExtensionFraction. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read requiredExtension, margin, feasible. Inspect feasible before interpreting the associated values.

Require positive relaxed length, nonnegative insertion length and maximum extension fraction. Return relative extension, maximum-minus-required margin, and supplied-limit feasibility.^[1]

Input field	Meaning and units	Accepted input
relaxedLength	Relaxed Length	Required. Finite number; strictly above 0.
insertionLength	Insertion Length	Required. Finite number; minimum 0.
maxExtensionFraction	Max Extension Fraction	Required. Finite number; minimum 0.

Output field	Interpretation	Returned shape
requiredExtension	Required Extension	Required. Finite number.
margin	Signed allowance under the subtraction order above.	Required. Finite number.
feasible	Feasible	Required. Boolean.

json

{
  "input": {
    "relaxedLength": 40,
    "insertionLength": 60,
    "maxExtensionFraction": 0.75
  },
  "output": {
    "requiredExtension": 0.5,
    "margin": 0.25,
    "feasible": true
  }
}

Limitations and assumptions

Required extension can be negative when insertion is shorter. The caller's limit is not a tested material limit or an assessment of garment comfort and safety.
Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.

Alternative or Complementary methods

Test the intended material and review the complete pattern fit. Account for recovery, shrinkage, directional stretch and construction instead of interpreting a length ratio as guaranteed comfort or suitability.

References

Calculation and input contract: fashion/elastic-insertion-stretch-limit-gap — tool.io

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