====== Parameters Page ======

A parameter, as defined in Ecolego, is a constant nominal value. For probabilistic analysis, probability density functions can be assigned for uncertain parameters.

===== User interface =====

To the left is a listing of all available parameters. When you select a parameter in the list, information (such as unit) and values for the parameter is displayed in the table to the right.

===== The list of parameters =====

The list presents all available parameters. Below the list is a section where you can search for specific parameters:

  * **Name** - Enter the name, or part of the name.
  * **Category** - Select a category for the parameter. The categories are part of the model, so this list is empty unless the model creator has assigned categories to the options.
  * **Sub-system** - Select a sub-system to only display parameters for a specific model component.

===== Assigning parameter data =====

==== Information ====

The information section details specifics about the parameter. The description box can give you information about the data to enter, and the unit box tells you which unit is expected.

==== Entering data ====

The first column(s) of the table list indices for the parameter. For a contaminant-dependent (vector) parameter, the first column lists each contaminant. The subsequent columns allow you to enter values, probability density functions etc. When you click a cell in the **Value** or **PDF** column, an tool appears below the table.

==== Entering (nominal) values ====

The tool that appears when you click a cell in the **Value** table can help you convert a value to the unit required of the model.

  - Enter the unit for the value you have in the **From** box.
  - Enter your value in the **Value** box.
  - Enter the target unit in the **To** box. This unit should be the same as listed in the **Unit** box in the **Information** section.
  - Click apply to put the converted value in the cell.

==== Entering a probability density function (PDF) ====

Click a cell in the **PDF** column. Choose a probability density function from the **Distribution functions** drop-down list. Input fields will appear depending on the number of arguments required for the selected function.

The **Upper trunc** and **Lower trunc** fields are always available and can be used to truncate the function.

The editor contains several tools. By using the buttons in the toolbar you can select which tool to show.

===  Chart ===

The chart tool displays a graph of the current function. By using the buttons on the left hand side you can choose to plot

  * The PDF (Probability density function)
  * The CDF (Cumulative distribution function)
  * The survival function
  * The hazard function
  * The cumulative hazard function

Delimitors and calculated values from the **Calculation** tool are displayed in the graph using markers.

===  Properties ===

Displays statistics on the currently selected function.

===  Calculation ===

Allows you to calculate values and percentiles for the current function. These values are marked in the graph of the **Chart** tool.

===  Information ===

Describes the currently selected function and it’s parameters.

===== References =====

  * [[Introduction_to_Ecolego_Player|Introduction to Ecolego Player]]
  * [[Ecolego_Player_Wiki|Ecolego Player Wiki]]