Free Water Fraction Calculator
Qualified Free Water Fraction Calculator mixture fraction only, compartmentidentifiability, T2correction and acquisition model external; actual compatible definitions and matching units required, no causal efficacy/diagnosis or safety claim.
Description
A fitted water-compartment fraction depends on the acquisition, compartment definition and identifiability of the model.
A fitted water-compartment fraction depends on the acquisition, compartment definition and identifiability of the model.1
This tool divides supplied fitted quantities without fitting the model or enforcing a physical fraction interpretation.
When to use Free Water Fraction Calculator
This tool divides supplied fitted quantities without fitting the model or enforcing a physical fraction interpretation.
How to use Free Water Fraction Calculator and how it works
- Prepare independently fit named water compartment signal fraction numerator, independently fit total water signal fraction denominator, using the input definitions and matching units below.
- Enter the required fields and run Free Water Fraction Calculator.
- Read result.value using the units, signs and ordering explained below.
- Correct any rejected inputs and rerun; interpret the result within the stated model and its assumptions.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualIndependentlyFitNamedWaterCompartmentSignalFractionNumerator | Actual Independently Fit Named Water Compartment Signal Fraction Numerator. Use the units and matching context stated in the calculation below. | number | Required; nonnegative; finite; other constraints below |
| actualIndependentlyFitTotalWaterSignalFractionDenominator | Actual Independently Fit Total Water Signal Fraction Denominator. Use the units and matching context stated in the calculation below. | number | Required; strictly positive; finite; other constraints below |
Require nonnegative independently fitted named-compartment numerator and positive fitted total-water denominator on the same signal basis. Return their dimensionless ratio without enforcing numerator<=denominator or clipping to one. The compartment model, identifiability and T2 correction are external; input inconsistency can yield a value above one.
conditionalWaterRatio=fittedCompartmentNumerator/fittedTotalDenominator Apply the input ordering, units and branch conditions stated above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the calculated or selected fields below. | object |
| result.value | Numeric model result on the ratio, score, constant or density basis explained above. | number |
{
"input": {
"actualIndependentlyFitNamedWaterCompartmentSignalFractionNumerator": 2,
"actualIndependentlyFitTotalWaterSignalFractionDenominator": 4
},
"output": {
"result": {
"value": 0.5
}
}
}Limitations and assumptions
The calculation uses the supplied observations and model inputs. It does not collect measurements, select a reference population or coefficient, or establish that the model applies to the actual case. The stated branch conditions and output units remain part of the result.
All fields require explicit values. Unexpected fields, wrong types, nonfinite numbers and sparse arrays are rejected. Alignment, bounds and supported-token rules are explained above; extremely large inputs or nonfinite results can also fail. Input errors differ from successful false comparisons, unavailable-domain flags and empty match lists.
Alternative or Complementary methods
Use Neurite Density Index Calculator for a complementary operation: A neurite-density index depends on the diffusion acquisition, compartment model and parameter interpretation.
Use Radial Kurtosis Calculator for a complementary operation: Radial diffusion kurtosis depends on tensor fitting and the direction convention perpendicular to a qualified axis.
References
-
Free Water Fraction Calculator — tool.io
Similar or alternative tools
- Neurite Density Index Calculator
A neurite-density index depends on the diffusion acquisition, compartment model and parameter interpretation.
- Radial Kurtosis Calculator
Radial diffusion kurtosis depends on tensor fitting and the direction convention perpendicular to a qualified axis.