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Number of points on a plot/ number of "nodes"

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Hi. I am trying to compare two plots to each other. To do so, I am exporting both of the plot data and then subtracting the datasets in excel. However, the plots have a different number of points or "nodes", and I can't figure out how to change the number of points. I need the plots to have the same number of data points for comparison. The simulations are exactly the same expect one of the simulations has a small piece of stainless steel added in. Please let me know.


3 Replies Last Post Nov 9, 2022, 3:46 a.m. EST
Mark Cops COMSOL Employee

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Posted: 2 years ago Nov 8, 2022, 9:39 a.m. EST

Dear Victoria, It sounds like you have two different studies and want to compare the results from both. I wonder if using the Join Dataset might work for you? You can take the difference between 2 solution datasets and plot it directly in COMSOL. This is described here: https://www.comsol.com/blogs/join-solutions-comsol-multiphysics/ . One example where this is used is here: https://www.comsol.com/model/axisymmetric-transient-heat-transfer-267

Best,

Mark

Dear Victoria, It sounds like you have two different studies and want to compare the results from both. I wonder if using the Join Dataset might work for you? You can take the difference between 2 solution datasets and plot it directly in COMSOL. This is described here: https://www.comsol.com/blogs/join-solutions-comsol-multiphysics/ . One example where this is used is here: https://www.comsol.com/model/axisymmetric-transient-heat-transfer-267 Best, Mark

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Posted: 2 years ago Nov 8, 2022, 11:06 a.m. EST

Hi Mark,

Thank you for the reply. It is not two different studies, but it is two different geometries. The geometries are exactly the same except one geometry has a little piece of stainless steel in it. I basically want to compare the results with and without this piece of stainless steel, so to do this, I first get the data with the piece of stainless steel in the geomtry, and then I go and disable that piece and its material and recompute. When I export the data, the data with the stainless steel piece has more data points than the one without. I am wondering if there is a way that I can manually set how many data points I want plotted?

Hi Mark, Thank you for the reply. It is not two different studies, but it is two different geometries. The geometries are exactly the same except one geometry has a little piece of stainless steel in it. I basically want to compare the results with and without this piece of stainless steel, so to do this, I first get the data with the piece of stainless steel in the geomtry, and then I go and disable that piece and its material and recompute. When I export the data, the data with the stainless steel piece has more data points than the one without. I am wondering if there is a way that I can manually set how many data points I want plotted?

Gunnar Andersson COMSOL Employee

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Posted: 2 years ago Nov 9, 2022, 3:46 a.m. EST

Most plots have a Quality section in the Settings window. I think that setting Smoothing=No smoothing and maybe also Resolution=No refinement or Custom will make it possible for you perform the comparison. The Smoothing setting matters as it when enabled will merge points that have the same coordinates and data values. When you introduce the stainless steel I suspect that less smoothing will be possible and that you therefore get more points in the exported plot data.

Most plots have a Quality section in the Settings window. I think that setting Smoothing=No smoothing and maybe also Resolution=No refinement or Custom will make it possible for you perform the comparison. The Smoothing setting matters as it when enabled will merge points that have the same coordinates and data values. When you introduce the stainless steel I suspect that less smoothing will be possible and that you therefore get more points in the exported plot data.

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