Description
Multiply the selected left or right endpoint flow by nonnegative intervalSeconds for stepVolume.
Flow calculations relate volume, time, cross-section, velocity, and supplied model parameters. A local ratio or contribution does not by itself solve a complete hydraulic system.
Multiply the selected left or right endpoint flow by nonnegative intervalSeconds for stepVolume.
When to use this tool
Use Hydrograph Step Average Instantaneous Reference when you need one explicit flow component with coherent units and references.
How to use the tool and how it works
- Enter firstFlow, secondFlow, intervalSeconds, leftStep. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read stepVolume, trapezoidVolume, volumeDifference. Use the output convention below.
Multiply the selected left or right endpoint flow by nonnegative intervalSeconds for stepVolume. Compare with the trapezoidal mean-flow volume and return step minus trapezoid.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| firstFlow | First Flow | Required. Finite number. |
| secondFlow | Second Flow | Required. Finite number. |
| intervalSeconds | Interval Seconds | Required. Finite number; minimum 0. |
| leftStep | Left Step | Required. Boolean. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| stepVolume | Step Volume | Required. Finite number. |
| trapezoidVolume | Trapezoid Volume | Required. Finite number. |
| volumeDifference | Volume Difference | Required. Finite number. |
{
"input": {
"firstFlow": 2,
"secondFlow": 6,
"intervalSeconds": 10,
"leftStep": true
},
"output": {
"stepVolume": 20,
"trapezoidVolume": 40,
"volumeDifference": -20
}
}Limitations and assumptions
- Flows are signed volume per second on one basis; the comparison is a quadrature convention, not evidence that either interpolation matches unobserved flows.
- 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 surveyed geometry, appropriate calibration, and a complete hydraulic model for operational or design decisions.
References
Similar or alternative tools
- Hydrograph Segment Volume Trapezoid
Average startFlowM3PerSecond and endFlowM3PerSecond and multiply by nonnegative durationSeconds for volumeM3.
- Hydrograph Time Centroid Term
Multiply nonnegative discharge by interval for volume and multiply that by time for firstMoment.