====== Tutorial 4 - Index operators ======

===== 4/5 =====

In this lesson you will learn how to use an [[Index_operation|Index operation]] to find the maximum concentration of contaminants in the plants.

**Overview**

An [[Index_operation|Index operation]] block is used to calculate the sum, product, minimum or maximum value of a vector or matrix block or parameter.

  - Open the [[Blocks_window|Blocks window]].
  - Right-click the window and select **Create | Index Operation** from the pop-up menu.
  - Edit the new [[Index_operation|Index operation]] block.
  - In the **Properties** tab, rename the block to “Plant_Max”. Give it the full name “Maximum Plant Concentration”.
  - Select the **Values** tab. Choose “Maximum” from the **Operation** drop down list.
  - In the table, select “Plant”.
  - //Plant// is a matrix and the [[Index_operation|Index operation]] can only perform over one index list. In the **Index list** drop down list, make sure that “Plants” is selected. This will calculate the maximum value for each material.
  - Click **Ok** to close the window.

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**Next**

  * [[Tutorial_4-Running_the_simulation|Running the simulation (5/5)]]

**Previous**

  * [[Tutorial_4-Creating_expressions_and_parameters|Creating expressions and parameters (3/5)]]

**References**

  * [[Tutorials|Back to Tutorials]]
  * [[start|Home]]