Sediment Bin Width Factor Tool

Description

Use upperSize-lowerSize for linear width or ln(upperSize/lowerSize) for log width, then divide mass by that width.

Sediment and soil calculations distinguish mass basis, solid density, bulk volume, and grain-size conventions. Changing moisture or grain-size scale changes the denominator or coordinate, not the physical sample itself.

Use upperSize-lowerSize for linear width or ln(upperSize/lowerSize) for log width, then divide mass by that width.

When to use this tool

Use Sediment Bin Width Factor when you need an explicit sediment or material-basis conversion.

How to use the tool and how it works

Enter lowerSize, upperSize, suppliedBinMass, useLogWidth. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read width, massPerWidth. Use the output convention below.

Require positive ordered size bounds and nonnegative suppliedBinMass. Use upperSize-lowerSize for linear width or ln(upperSize/lowerSize) for log width, then divide mass by that width.^[1]

Input field	Meaning and units	Accepted input
lowerSize	Lower Size	Required. Finite number; strictly above 0.
upperSize	Upper Size	Required. Finite number.
suppliedBinMass	Supplied Bin Mass	Required. Finite number; minimum 0.
useLogWidth	Use Log Width	Required. Boolean.

Output field	Interpretation	Returned shape
width	Upper minus lower size or natural-log size ratio under useLogWidth; not a phi-bin width.	Required. Finite number.
massPerWidth	Mass Per Width	Required. Finite number.

json

{
  "input": {
    "lowerSize": 1,
    "upperSize": 3,
    "suppliedBinMass": 8,
    "useLogWidth": false
  },
  "output": {
    "width": 2,
    "massPerWidth": 4
  }
}

Limitations and assumptions

Linear output is mass per size unit and logarithmic output is mass per natural-log interval, not phi-bin density; units and sampling basis must match and no size distribution is inferred.
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

Use a traceable laboratory and sampling method for the required material property. Align wet/dry basis, solid versus bulk density, grain-size scale, and interval definitions before comparing samples.

References

Calculation and input contract: geomorphology/sediment-bin-width-factor — tool.io

Similar or alternative tools

Grain Size Support Share
Sum mass only for bins fully inside that interval and divide by total mass, otherwise return zero with defined false.
Grain Size Phi Uncertainty Width Transform
Compute phi as negative log2 of the numeric diameter in millimeters, reverse diameter extrema for phi bounds, and return logarithmic width.