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Parameter Editor [HGA+ only]


The Parameter Editor allows you to define and manage parameters in your project. You can open the Parameter Editor from the Modules menu or click on the button in the main toolbar. The Parameter Editor will appear as a tab in the main Hydro GeoAnalyst view, as shown in the following example:


Please Note: If you save any changes to one ore more Parameters, Hydro GeoAnalyst automatically reload your project,  which includes resetting your views and prompting you to save changes to other modules. On opening the Parameter Editor, you will receive a prompt like the following to acknowledge that changes will force a project reload.



On the left side of the tab you will find a list of parameters that can be filtered using a dropdown list of the Parameter Groups and the standard filter bar in Hydro GeoAnalyst. The right side of the Parameter Editor window provides the tools to manage the selected parameter and its associated metadata using the relevant forms and the following buttons on the parameter editor toolbar:


Parameter Editor Toolbar

The Parameter Editor toolbar contains the following controls:



Parameter: Displays the name of the currently selected parameter.

Save: saves changes to the currently selected parameter.

Delete: deletes the currently selected parameter.

Add Parameter: adds a new parameter from the Chemical List or (if Modeled Parameters are selected) from the default thermodynamic database.

New Parameter: adds a new blank parameter to the project.

Add Parameters from List: adds one or more parameters in a specified list by searching the Chemical List for matches.

New Parameter: adds a new blank parameter to the project.

Delete All unused parameters: adds one or more parameters in a specified list by searching the Chemical List for matches.


Parameter Information

Information about all measured parameters is managed below the Parameter Editor toolbar and stored in the Parameter Table. Parameter metadata information includes the relevant chemical and descriptive attributes as follows (using bicarbonate as an example):

Short Name: a unique, typically short or abbreviated, name that is easily recognizable (e.g. HCO3) and used as a look up name and a primary key

Display Name: a longer descriptive name (e.g. bicarbonate) used for labeling in plots and tables

CAS: Chemical Abstracts Service (CAS) Registry number (e.g. 56240-83-6), a unique number assigned by CAS, a division of the American Chemical Society.

Description: typically a more descriptive name that may include a list of alternate names (e.g. bicarbonate; hydrogencarbonate)

Formula: chemical formula (e.g. HCO3)

Molecular Weight: combined atomic weights of all constituent atoms that compose the parameter (e.g. HCO3 = 1x1.00794 + 1x12.0107 + 3x15.9994 = 61.01684 g/mol)

Valency: the ionic/electric charge of the parameter in solution (e.g. -1).


Custom Calculated Parameters

The check box next to the label "Allow value of this parameter to be created or updated by the parameter calculator" allows you to enable the Parameter Calculator for the specified parameter.


Modeled Parameters

Hydro GeoAnalyst allows you to calculate saturation indices, activities, and a few additional/common parameters using the integrated connection with PHREEQC based on the the default thermodynamic database. In order to calculate values for these parameters, they must be first added to the project. To add modeled parameters to the project,

set the Parameter Group dropdown to "Modeled",

click the Add parameter button, and

select one or more parameters using the PHREEQC parameter selection window that appears.



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