> For the complete documentation index, see [llms.txt](https://help.auxalia.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.auxalia.com/plant-tools/plantexpresstools/how-to-use/calculations/update-calculations.md).

# Update Calculations

If calculations are configured the calculations can be updated either through the ribbon...

![](/files/ETDRhNj8910JM1cCnF6i)

... or the calculations will be updated when the drawing is saved. For this the checkbox under "Calculations Update" must be check under the settings [On Drawing Save](/plant-tools/plantexpresstools/settings/on-drawing-save.md).

In the following chapters we will see the following examples:

1.The property "MeasuringType" will be calculated by getting the first character of the property "Type" ([Calculate simple Example](/plant-tools/plantexpresstools/how-to-use/calculations/calculate-simple-example.md)).

2.The color of the "GeneralInstrumentSymbols" will be changed to red if the Tag contains a "?" ([Calculate AutoCAD Properties)](/plant-tools/plantexpresstools/how-to-use/calculations/calculate-autocad-properties.md).

3.The line annotation will be calculated to show in a flexible way the values of the properties "InsultationType" and "InsulationThickness" ([Calculate Annotations)](/plant-tools/plantexpresstools/how-to-use/calculations/calculate-annotations.md).

4.The Operational Flow Speed and Size will be calculated based on Design Flow Speed and Flow Rate, This example will also include PlantLink ([Calculate FlowData (complex) with PlantLink)](/plant-tools/plantexpresstools/how-to-use/calculations/calculate-flowdata-complex-with-plantlink.md).

![](/files/FhENbxd4KTm8EcTc4B5G)