# 3.9.16: User Iso-Lines and Stream-Lines

![Fig.3.9.16.1: User defined Iso-lines (red) and stream-lines (green) on a rectangular shell patch](/files/-MCkEaZLifppRqqwXty8)

{% hint style="info" %}
The definition “User\_Iso\_Lines.gh” can be found in the Karamba3D installation folder under “..- Examples/TestExamples/”. Double-click on the Karamba3D desktop icon to get there.
{% endhint %}

Both components **“User Iso-Lines”** and **“User Stream Lines”** work similar to the **“IsoLines”**- (see section [3.6.12](/3-in-depth-component-reference/3.6-results/3.7.3-results-on-shells/3.6.12-line-results-on-shells.md#isolines-on-shells)) and **“Principal Stress Lines on Shells”**-components (see section [3.6.12](/3-in-depth-component-reference/3.6-results/3.7.3-results-on-shells/3.6.12-line-results-on-shells.md#principal-stress-lines-on-shells)) respectively. The only difference lies in the fact that for each node of the model (which includes also nodes that only connect to beams) a value (input-plug **“Vals”**) or vector (input-plug **“TVecs”**) tangent to the flow needs to be supplied.

{% file src="/files/QVHTS3T3j4Hzj3aW0bEu" %}


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