# Variable System In dialog boxes, values are entered as fixed inputs. However, it is often necessary to be able to change a value “from the outside” or to define values depending on other values. A system of variables is required for this. Instead of the value for, for example, a cross-section height of a component, the variable is entered. At another point, for example in the default values of a structure, a value is assigned to this variable. Through the variable, the concrete value is now transferred from the default value to the cross-section height without the cross-section height having to be edited in the dialog. Other variables are already provided and assigned by the system, for example the thickness of a wall layer. In addition, variables can also be calculated in formulas. * The variable system is used equally for default values, point symbols, HRB, and combined elements. * In the respective editors, the properties of the variables are defined in the **Variable definition** . When querying the default values, inserting a point symbol, or inserting a combined element, the defined variables are displayed and their values can be changed. This dialog is the **variable query**. ### User variables * The variables defined by the user are also **User variables** called. In contrast, the **system variables** are defined in the system and cannot be changed. * The user variables can be freely defined. > - They only need to start with “V” so that there are no overlaps with system variables. This makes the variables easier to handle and identify. Example: “VKT” as the variable for notch depth. > - In the file name, only the digits 0 to 9, letters, and the underscore may be used. The use of spaces, operators (+, -, \*, /), punctuation marks, parentheses, or other special characters is not permitted. > - Upper and lower case are distinguished; **Vab** is therefore a different variable from **VAB**. However, it is not recommended to distinguish variables in this way. * The variables can be grouped. If more than one variable group is present in the variable query, a subdialog is offered for each variable group. This is opened via a button with the group name. For each variable group, this button is automatically created above the variables. * The variables can be documented and explained through additional descriptions and help images. These appear both during the query and when inserting the variables into formulas. * The variables are managed using variable sets with the standard procedure. A variable set consists of the definitions of one or more variables. A variable set can be saved and reused elsewhere. Transfer via data exchange and email is also possible. When importing variable sets, either all existing variables can be replaced or only new ones added. ### Dietrich’s standard variables Dietrich’s software supplies a large number of settings that are already based on user variables. These user variables are a standard supplied by Dietrich’s, namely Dietrich’s standard variables. Like all user variables, they can be freely edited and therefore cannot be locked or protected in any way. To avoid conflicts and overwriting, the following rules should be observed: 1\) Dietrich’s standard variables always begin with “V\_”, i.e. a “V” and an underscore. Your user variables should therefore never begin with “V\_”. 2\) You can and should also use Dietrich’s standard variables in your queries and settings. However, the meaning of the variable should never be changed. #### Dietrich’s standard default values We supply an extensive and coherent collection of default values and settings based on them for roof, wall, ceiling, framework, and tools. The default values used there are called “Dietrich’s standard default values”; they are based on Dietrich’s standard variables. For these settings to be used meaningfully at all times, the “Dietrich’s standard default values” must be loaded. They should therefore be loaded in the default values so that they can be queried and used as user variables. However, if one does not want so many or different user variables in the query, then not all of Dietrich’s standard default values are included there. To ensure that the settings still have meaningful values in the formulas, the remaining Dietrich default values are loaded automatically. In the formula editor, these can then be found in the tree element under “Dietrich’s standard default values”; the standard default values that were loaded in the default values are found under “User variables”. ### system variables System variables contain certain values that are provided by the system. They depend on the objects currently available. For example, the variable Lp0 indicates the layer thickness of layer 0 of the current wall. The available system variables are offered in the formula editor. There, the system variables are documented through descriptions and help images. ### Hierarchy of variables * The variable system is fundamentally continuous across all levels. A variable defined in the project can also be used in the structure, as well as in point symbols, combined elements, or HRB files. * Variables as default values are passed from one stage to the next, with the last assignment taking precedence: > - If, for example, a post width of 0.06 is defined in a project, it can be accessed from any structure in this project and the posts receive a width of 0.06 m. If the same variable is then entered again in one of the structures and a post width of 0.08 is assigned, the posts in this structure receive a width of 0.08 m, while they continue to receive 0.06 m in the other structures. > - An HRB assignment in this structure can also use this variable and adopt the post width of 0.08. However, if the variable in the HRB file is assigned 0.10, then a post width of 0.10 is used in the HRB assignment. * The “external” identifier reverses this order. > - For example, in a structure, a variable is used to define the post width as 0.06; this variable is assigned the identifier external. Now the post in this structure will receive the width of 0.06 m. However, if the post width is defined in the project with the same variable as 0.12, then the posts in the structure are created with a post width of 0.12. The value of the variable adopted from outside, in this case from the project, has higher priority. > - An HRB assignment that uses this variable with the identifier “external” will likewise not use the value from the HRB file, but rather the value from the structure or project. > - The identifier external is also used to define default values for a variable. The variable receives the default value if no different value is specified externally. This ensures, for example in an HRB file, that the variable has a usable value even if the variable was not defined in the structure or project. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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