# Sum up scalar along the path of a StreamTracer

**URL:** https://discourse.paraview.org/t/sum-up-scalar-along-the-path-of-a-streamtracer/3143
**Category:** ParaView Support
**Created:** [December 9, 2019, 7:45am UTC](https://discourse.paraview.org/t/sum-up-scalar-along-the-path-of-a-streamtracer/3143 "2019-12-09T07:45:52Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![fantasio](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/f/bc8723/32.png) [@fantasio](https://discourse.paraview.org/u/fantasio)
#### Post date: [December 9, 2019, 7:45am UTC](https://discourse.paraview.org/t/sum-up-scalar-along-the-path-of-a-streamtracer/3143/1 "2019-12-09T07:45:52Z")

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Hi,  
i want to use the StreamTracer and sum up the values of a point value along its streamlines. So along of one streamline, the longer the path becomes, the sum increases. Next is i want to visualize the new calculated values in ParaView, i don’t know how to do this. The scalars are from postProcessing in OpenFOAM.

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### Author: ![mwestphal](https://discourse.paraview.org/user_avatar/discourse.paraview.org/mwestphal/32/17_2.png) [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [December 9, 2019, 10:25am UTC](https://discourse.paraview.org/t/sum-up-scalar-along-the-path-of-a-streamtracer/3143/2 "2019-12-09T10:25:34Z")

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You can’t do that directly with the stream tracer, but it is quite easy to do the integration along the lines with a Programmable Filter after the stream tracer.