Cloning HMS Components

Quick Start

from hms_commander import init_hms_project, hms
from hms_commander import HmsBasin, HmsMet, HmsControl, HmsRun

init_hms_project("project")

# Clone components
HmsBasin.clone_basin("Baseline", "Updated_Basin", hms_object=hms)
HmsMet.clone_met("Baseline_Met", "Atlas14_Met", hms_object=hms)
HmsControl.clone_control("Jan2020", "Jun2020", hms_object=hms)
HmsRun.clone_run("Run_Baseline", "Run_Updated", hms_object=hms)

Primary Sources

Code:

• hms_commander/HmsBasin.py#clone_basin()

• hms_commander/HmsMet.py#clone_met()

• hms_commander/HmsControl.py#clone_control()

• hms_commander/HmsRun.py#clone_run()

Rules:

.claude/rules/hec-hms/clone-workflows.md

- CLB Engineering approach

Examples:

examples/clone_workflow.ipynb

- Complete QAQC workflow

When to Use This Skill

• Setting up QAQC comparison workflows (baseline vs updated)
• Creating scenario alternatives without modifying originals
• Parameter sensitivity testing (multiple variations)
• Preserving working models before experiments
• Atlas 14 precipitation updates (keep TP40 baseline)
• Model calibration (test different parameter sets)

CLB Engineering LLM Forward Approach

Three Principles:

1. Non-Destructive: Preserves original components
2. Traceable: Updates description with clone metadata
3. GUI-Verifiable: Clones appear in HEC-HMS GUI immediately

Why This Matters:

QAQC workflows require side-by-side comparison in the HMS GUI:

• Baseline run → Baseline DSS file
• Updated run → Updated DSS file
• Compare hydrographs visually in HMS
• Verify changes are intentional

See:

.claude/rules/hec-hms/clone-workflows.md

for complete pattern

Core Capabilities

1. Basin Cloning

HmsBasin.clone_basin(
    template="Baseline",
    new_name="Updated_Basin",
    description="Updated with Atlas 14 precip",
    hms_object=hms
)

Result:

• New .basin file created
• Description includes clone metadata
• Appears in HMS GUI's Basin Manager
• All parameters copied from template

2. Met Model Cloning

HmsMet.clone_met(
    template="TP40_Met",
    new_name="Atlas14_Met",
    description="Updated to Atlas 14 depths",
    hms_object=hms
)

Result:

• New .met file created
• Gage assignments preserved
• Ready for precipitation updates

3. Control Specification Cloning

HmsControl.clone_control(
    template="Jan2020",
    new_name="Jun2020",
    hms_object=hms
)

Use case: Same model, different time periods

4. Run Cloning (Critical for QAQC)

HmsRun.clone_run(
    source_run="Baseline",
    new_run_name="Updated",
    new_basin="Updated_Basin",
    new_met="Atlas14_Met",
    output_dss="results_updated.dss",
    description="Atlas 14 update QAQC",
    hms_object=hms
)

Result:

• New run configuration
• Points to cloned basin/met
• Separate DSS file (critical for comparison!)
• Appears in HMS Compute menu

Common Workflows

Workflow 1: Atlas 14 Update QAQC

init_hms_project("project")

# 1. Clone met model
HmsMet.clone_met("Baseline_Met", "Atlas14_Met", hms_object=hms)

# 2. Update Atlas 14 depths
new_depths = [2.8, 3.5, 4.2, 4.9, 5.7, 6.5]
HmsMet.set_precipitation_depths("project/Atlas14_Met.met", new_depths)

# 3. Clone run with new met
HmsRun.clone_run(
    source_run="Baseline",
    new_run_name="Atlas14_Update",
    new_met="Atlas14_Met",
    output_dss="results_atlas14.dss",
    hms_object=hms
)

# 4. Execute both runs
HmsCmdr.compute_parallel(["Baseline", "Atlas14_Update"])

# 5. Compare in HMS GUI
# Open both DSS files side-by-side

Workflow 2: Parameter Sensitivity

# Test multiple curve numbers
for cn in [70, 75, 80, 85, 90]:
    # Clone basin
    HmsBasin.clone_basin("Baseline", f"CN{cn}", hms_object=hms)

    # Update curve number
    HmsBasin.set_loss_parameters(f"project/CN{cn}.basin", "Sub1", curve_number=cn)

    # Clone run
    HmsRun.clone_run(
        "Baseline_Run",
        f"Run_CN{cn}",
        new_basin=f"CN{cn}",
        output_dss=f"results_cn{cn}.dss",
        hms_object=hms
    )

# Execute all runs in parallel
HmsCmdr.compute_parallel([f"Run_CN{cn}" for cn in [70, 75, 80, 85, 90]])

Workflow 3: Scenario Comparison

scenarios = ["Baseline", "Alternative_1", "Alternative_2"]

for scenario in scenarios[1:]:  # Skip baseline
    # Clone all components
    HmsBasin.clone_basin("Baseline", f"{scenario}_Basin", hms_object=hms)
    HmsMet.clone_met("Baseline_Met", f"{scenario}_Met", hms_object=hms)
    HmsRun.clone_run(
        "Baseline_Run",
        f"Run_{scenario}",
        new_basin=f"{scenario}_Basin",
        new_met=f"{scenario}_Met",
        output_dss=f"results_{scenario}.dss",
        hms_object=hms
    )

    # Modify scenario-specific parameters
    # ...

Reference Files

• reference/clone_basin.md

  - Complete HmsBasin.clone_basin() API

• reference/clone_met.md

  - Complete HmsMet.clone_met() API

• reference/clone_run.md

  - Complete HmsRun.clone_run() API

• examples/qaqc_workflow.md

  - Complete QAQC setup

Related Skills

• parsing-basin-models - Modify cloned basins
• updating-met-models - Modify cloned met models
• executing-hms-runs - Run cloned scenarios
• extracting-dss-results - Compare results from clones