Assignment Filters

To display this screen:

You use this screen to define assignment filters. Assignment filters are used to assign different formulae for production and text fields for groups of tasks.

An Assignment Filter defines which tasks and/or resources are eligible to be included during the assignment process. It does this by only permitting a task or resource to be assigned if it passes supplied filter conditions.

It restricts the scope of scheduling by applying user-defined criteria, ensuring that only relevant tasks and resources are considered.

Assignment filters help improve scheduling accuracy, performance, and control by preventing unintended assignments

Filters can be generated manually or automatically. Each assignment filter can contain one or more conditions, for example "Assignment Type = 'Required' AND Task Type = 'Fixed Rate'".

Note: Assignment filters can only be used to limit the number of rows displayed in the Crosstab and resource bar chart views respectively.

What an Assignment Filter Does

An Assignment Filter:

  • Limits which tasks are eligible for assignment.

  • Limits which resources can be assigned.

  • Controls which combinations are considered during automatic assignment or optimisation.

  • Reduces the scheduling search space.

  • Ensures assignments comply with operational rules.

The filter is applied during the assignment process and affects scheduling logic — not just what is displayed on screen.

Why Use an Assignment Filter?

Assignment Filters are typically used to:

  • Separate operational areas (e.g., Surface vs Underground).

  • Restrict assignments by equipment type.

  • Prevent cross-project resource allocation.

  • Limit scheduling runs to a defined subset of tasks.

  • Improve performance in large schedules.

Assignment Filters Toolbar

The following tools appear along the top of the screen:

  1. Add a new new filter. The default naming convention for filters is New Filter # where # represents an incremental index.

  2. Copy the selected filter to create a new one. Useful for creating filters that are similar.

  3. Delete the selected filter.

    Warning: You are not asked to confirm deletion, and this cannot be undone. Use carefully!

  4. Rename the selected filter.

  5. Apply the currently selected filter to items in the Task Bar chart.

  6. Generate filters automatically using the Generate Filters screen.

To define a new assignment filter:

  1. Display the Filters screen.

  2. Click Add.

  3. Edit the default Filter name to something useful.

  4. Check Show Summary so that, if you have grouping defined, summary bars for the grouped tasks are automatically displayed when the filter is active. If unchecked, they are not displayed.

  5. Check In List to ensure this filter is shown in all lists where filter selections are made, for example the Task Filter toolbar, production field formulae and so on. If unchecked, the filter is not displayed.

  6. Use Group to create or add a filter to a nominal group on this screen. This is to make the ordering and categorizing of filters on this screen more interactive. By default, Group is empty, meaning the filter is listed at the 'top level'. Enter any value to the field to either add the filter to a new group, or an existing one.

  7. Next, you need to define the filter expression(s) for the new filter:

    1. In the table on the left, leave And/Or for the first row empty (it is ignored anyway for the initial filter expression).

    2. Select the Field Name containing the values to control the filter.

      Tip: Start typing the name of the field to quickly jump to the field that you need.

    3. Use the Test field to decide how the Field Name value is compared with the Values field on the right. Standard comparison operators are listed: =, not =, <, <=,>,>=.

    4. What Value are you using to see if the filter expression is true or false? Where valid values are relevant (say, where the Field Name is Assignment Type), these display in a list, otherwise freeform text is entered.

  8. Use And/Or to add a second or subsequent condition to your filter, choose how the expressions are to be considered (if you don't need multiple expressions, skip this section):

    • Or – The filter passes if assignments pass either of the current and next expressions. For example, for the filter to include values that are either "Task Type = Fixed Rate" or "Task Type = Hammock".

    • And – The filter passes if both the current and next expression pass. For example, an assignment passes the filter if both "Task Type = Fixed Rate and Total Profit < 1000".

    Tip: Remember that And is generally less inclusive (and gives rise to fewer passes) than Or for the same expression conditions.

  9. Repeat the step above for each filter condition.

  10. Click OK.

  11. Save your project.

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