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Optimize¶

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QXL Monte Carlo > Monte Carlo > Optimize

Finds input settings for a goal you set on an output, optionally subject to constraints you set.

You say what "best" means and which inputs the Optimizer is allowed to move. It reports the settings it found and offers to run a full simulation at them.

What it can move¶

Only inputs you allowed. An input's Optimization section in the Mark Input dialog decides whether the Optimizer may change it, and an input marked No is never touched.

On the setup screens each input is one of three things: one the Optimizer is currently set to move, one that cannot be optimized at all, or one that could be but is not being optimized right now. The last two are counted on their own lines, with a Show names button beside each so the list can be read without taking up the screen when it is not wanted.

An input that cannot be optimized has no row in the ranges grid. It is counted on its own line under the grid:

1 input cannot be optimized.

A Custom Continuous, Custom Discrete or Empirical input can never be optimized.

The setup, in order¶

Optimize walks through screens rather than one dialog.

Screen 1, the goal and the constraints. What you are optimizing for, and any conditions the answer must satisfy.

Screen 2, the ranges. Which input parameters the Optimizer may change and between what bounds.

Both screens carry Save Optimizer Settings, which stores what you have set up so the next run starts from it, and confirms with Optimizer settings saved. Options... on the first screen opens five run settings.

Every control on both screens is on the Options page.

While it runs¶

Optimization in progress charts the best value of the goal's statistic found so far, with a dashed Target line for a Set target goal. Stop optimization ends the run and keeps the best answer found so far; Cancel abandons the run, which reports nothing.

The result¶

The settings the optimizer found

Optimizer Results has a table with one row per optimized parameter: Input, Parameter, Value now and Optimal value. A parameter that was Not Optimized has no row. Below it are Objective: (the goal as a sentence), Optimizer Results: (the goal's statistic at the answer, for example "Cpk of Outside width = 1.33") and Optimization Time:, then the question:

Would you like to replace the current input settings with the optimal values found during optimization?

Yes writes the optimal values into the inputs and No leaves them as they were. A tick box runs an ordinary simulation after Yes has written them:

Run Monte Carlo simulation at the optimal settings

A run stopped with Stop optimization also reaches this screen, with a statement that it was stopped early.

When the answer does not satisfy everything you asked for, the screen says so plainly rather than presenting it as a clean result:

NOTE: All constraints were not met.

What this page does not describe¶

How the Optimizer searches is not documented, deliberately. This page and its Options page say what the tool does, what every control means and what the output holds. They do not describe the search itself.

Options, for the goal, the constraints, the ranges and the five run settings.
Mark Input, where an input is allowed or forbidden to be optimized.