Changes in Optimization Settings may cause break in old input files (Plus New Feature)

[GabrielSoto-INL]

Hello everyone!
I wanted to bring attention to a new feature for HERON input scripts that could potentially break previous scripts when using optimization settings.

Changes to Optimization Settings

Previously, when running a HERON case in opt mode, a user could specify <optimization_settings> within the <Case> node. An optional entry within those settings was <metric> which allowed the user to select a statistic (e.g., "expectedValue", "valueAtRisk") applied to the set of NPV results from the inner runs. This is then used as the Outer objective function.

<!--old version-->
<Case name="Opt_Runs">
  <mode>opt</mode>
  <optimization_settings>
    <metric>expectedValue</metric>
  </optimization_settings>
  [...]
</Case>

For an old example of how this was used, see here (an old version of the optimization_settings test).

We have recently switched to a format that differentiates between a statistical metric and economic metric to optimize. The old <metric> node is now called <stats_metric>. Additionally, we now allow for an <opt_metric> to be chosen besides NPV. HERON currently supports:

1. NPV
2. PI (Profitability Index)
3. IRR (Internal Rate of Return)

Levelized Cost (implemented as the NPV_search option in TEAL) is coming soon! The new format looks like this:

<!--new version-->
<Case name="Opt_Runs">
  <mode>opt</mode>
  <optimization_settings>
    <stats_metric>expectedValue</stats_metric>
    <opt_metric>NPV</opt_metric>
  </optimization_settings>
  [...]
</Case>

New Feature for Economic Metrics

There is also a new node in the <Case> nodes for returning additional economic metrics at the end of your run, regardless of opt or sweep mode.

<Case name="Opt_Runs">
  <economics>
    <EconMetrics>
      <NPV/>
      <IRR/>
      <PI/>
    </EconMetrics>
    [...]
  </economics>
  [...]
</Case>

These (along with all statistics in <return_statistics> applied) are reported back in the final CSV file at the end of the run.

[j-bryan]

Thanks for the heads up on this change, Gabe. I'll pass the word along to the guys at USU.