Modifying the objective function using target charts

Target charts allow direct interaction with the indicators that have been chosen to drive the optimization model of Patchworks. A target chart is a control panel that displays current settings and facilitates adjustment of all of the target settings (see Figure 59, “Quick Tour of a Target Chart ”). Targets can either be Active or Inactive (or turned off), and their respective status directly influences the formulation of the solution. Targets only contribute to the scheduler's decision making process if they are Active. If the target is inactive (or turned off) it will not influence the scheduler's decisions. Active or not, all targets will continue to display the current conditions of the account values. If the target is Inactive the black bars will still track the value of the target (acting as an indicator instead of a target).

There are three activation icons on each Target Chart: Target, Maximum, Minimum. Each of these icons are colour coded to indicate which feature they control. Maximum is represented by blue and minimum is represented by red. The first target button controls if the target is active or not. The minimum and maximum active buttons independently control if minimum and maximum levels are active in the target.

Minimum values for each target can also be applied by checking and unchecking the Red check button on the toolbar. When a minimum value is applied the model attempts to find a solution which would satisfy the minimum conditions set for the specified account. If no minimum value is set the model is not forced to seek a solution in a particular direction based on that target. In the same respect maximum values can be applied, either in conjunction with a minimum or on their own, by using the blue check button on the toolbar.

By applying both a maximum and minimum value to a target the model would attempt to find a solution within the acceptable zone (grey). If either is applied individually the model is only constrained in one particular direction. If however neither constraints are applied, the model simply tracks the account as an "Indicator" (displaying current conditions) however it does not contribute to the solution of the model. For more detailed information regarding modelling with Targets see (LINK).


In the Patchworks world we sometimes use the terms 'account' and 'target' interchangeably. Accounts are structures that help sum block attribute values for a given geographic set of blocks. Targets represent the objectives that we provide to the scheduling model related to specific accounts. Accounts always have targets but often they are inactive. Targets can specify minimum and/or maximum account values by individual planning period. Targets are also used to identify weighting values used to trade off one target versus another. There is always a one-to-one correspondence between accounts and their associated target values.