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what's wrong with the new functionality "interpolation curve" when creating geometry ?
Posted Jan 4, 2012, 9:23 p.m. EST Geometry Version 4.2a 3 Replies
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(all the contents are in the .doc file, the original txt data for the interpolation curve is in the .xls file, the model is in the .mph file. Thanks)
Hi, everyone,
Recently, I have created a geometry using the “interpolation curve” (new functionality in 4.2a), but there are some problem puzzle me a lot. Could you do me a favor to give me some help and suggest? Thanks.
Original data and scatter plot
The data for the interpolation curve is obtained from the contour in the “Result”--> export into a file (.txt). All the original data are shown in the .txt file and unordered (I don’t why the extracted data is unordered). I plot all the data in other software using scatter plot, just shown in the Fig. 1.
Using the unordered data
Firstly, I used the above original data to as the input of the “interpolation curve”, while there is something wrong. When I mesh the domain, the “fail to insert point” error occurs just as Fig. 2 illustrated.
Then, I plot the point (47.3962, 4.99316) with the name of pt1 (the above error says where fail to insert point), just shown in the Fig. 3.
There is no obvious error in the geometry in the Geometry node, and the geometry is similar to the plot in Fig.1. However, when I turn to the material and physic nodes, the original geometry are quite different and baffling, just shown in the Fig. 4 and Fig. 5.
I am quite puzzled with the different geometry in the different nodes (Material node, Material node and the physics node). Why is there such difference? If there is a difference between different nodes, does it mean it is necessary to check the geometry in the Material or Physics node after creating the geometry in the Geometry node?
Using the ordered data
I have handled the data into x directional ascending order, and then use the “interpolation curve” to create the geometry. The Fig. 6, Fig. 7 and Fig. 8 show the geometry using closed curve, solid curve and open curve (type of the interpolation curve).
As we can see from Fig. 6 ~ 8, the both curve are different the input data. Furthermore, the geometry in the Geometry node and the Material node are quite different.
The theoretical plot using interpolation curve should be similar to the Fig. 1. Do I misunderstand the new functionality interpolation curve? What and how can I do to plot a line using such kind of data?
Thanks sincerely in advance for your help.
Best wishes to you and your family.
Hi, everyone,
Recently, I have created a geometry using the “interpolation curve” (new functionality in 4.2a), but there are some problem puzzle me a lot. Could you do me a favor to give me some help and suggest? Thanks.
Original data and scatter plot
The data for the interpolation curve is obtained from the contour in the “Result”--> export into a file (.txt). All the original data are shown in the .txt file and unordered (I don’t why the extracted data is unordered). I plot all the data in other software using scatter plot, just shown in the Fig. 1.
Using the unordered data
Firstly, I used the above original data to as the input of the “interpolation curve”, while there is something wrong. When I mesh the domain, the “fail to insert point” error occurs just as Fig. 2 illustrated.
Then, I plot the point (47.3962, 4.99316) with the name of pt1 (the above error says where fail to insert point), just shown in the Fig. 3.
There is no obvious error in the geometry in the Geometry node, and the geometry is similar to the plot in Fig.1. However, when I turn to the material and physic nodes, the original geometry are quite different and baffling, just shown in the Fig. 4 and Fig. 5.
I am quite puzzled with the different geometry in the different nodes (Material node, Material node and the physics node). Why is there such difference? If there is a difference between different nodes, does it mean it is necessary to check the geometry in the Material or Physics node after creating the geometry in the Geometry node?
Using the ordered data
I have handled the data into x directional ascending order, and then use the “interpolation curve” to create the geometry. The Fig. 6, Fig. 7 and Fig. 8 show the geometry using closed curve, solid curve and open curve (type of the interpolation curve).
As we can see from Fig. 6 ~ 8, the both curve are different the input data. Furthermore, the geometry in the Geometry node and the Material node are quite different.
The theoretical plot using interpolation curve should be similar to the Fig. 1. Do I misunderstand the new functionality interpolation curve? What and how can I do to plot a line using such kind of data?
Thanks sincerely in advance for your help.
Best wishes to you and your family.
Attachments:
- Interpolation curve in the geometry create.mph
- Fig.4 The geometry in Material node.png
- Fig.5 The geometry in the Physics node.png
- Fig.6 Closed interpolation curve.png
- Fig.7 Solid interpolation curve.png
- Fig.8 Open interpolation curve.png
- Fig.2 The error when mesh.png
- Fig.3 The error point, interpolation curve and a line in the Geometry node.png
- Fig.1 Scatter plot of the original data.png
- Original data-copy from the .txt file.xls
- What's wrong with the interpolation curve.doc
3 Replies Last Post Jan 8, 2012, 5:04 a.m. EST
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Posted:
1 decade ago
Hi
take a closer look at your data, you will notice its jumping back and forth with nm clearance, you need to better filter your points and get them ordered in a more regular way, I'm sure that will help ;)
--
Good luck
Ivar
take a closer look at your data, you will notice its jumping back and forth with nm clearance, you need to better filter your points and get them ordered in a more regular way, I'm sure that will help ;)
--
Good luck
Ivar
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
(all are in the .doc file, Thanks)
Hi, Ivar,
Thanks very much for your response.
After I encountered this problem, I found the data extracted from contour in the Result in the COMSOL using “export”. I have no ideas why the data jump back and forth. Afterward, I order the data and do the similar geometry again, but it fails again.
Solid interpolation curve is shown in the Fig. 1.
The open interpolation curve is strange, and the result is a straight line instead of a curve, just in Fig. 2 shown.
Is there something I missed or misunderstood?
Thanks for your response and guidance.
Best wishes to you and your family.
Hi, Ivar,
Thanks very much for your response.
After I encountered this problem, I found the data extracted from contour in the Result in the COMSOL using “export”. I have no ideas why the data jump back and forth. Afterward, I order the data and do the similar geometry again, but it fails again.
Solid interpolation curve is shown in the Fig. 1.
The open interpolation curve is strange, and the result is a straight line instead of a curve, just in Fig. 2 shown.
Is there something I missed or misunderstood?
Thanks for your response and guidance.
Best wishes to you and your family.
Hi
take a closer look at your data, you will notice its jumping back and forth with nm clearance, you need to better filter your points and get them ordered in a more regular way, I'm sure that will help ;)
--
Good luck
Ivar
Attachments:
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi
indeed it's slightly unexpected at first thoughts, but if yuo start to read the help file for interpolated function, you see that when closing the curve it's adapting the curve to get 1st and 2nd derivatives.
Your curve, that could as well be modelled by 3 points (at least it looks like that) is "converted to become smooth" and this gives the strange results.
I believe you are better off, re-reading the help file and asking support how to get your desired shape
--
Good luck
Ivar
indeed it's slightly unexpected at first thoughts, but if yuo start to read the help file for interpolated function, you see that when closing the curve it's adapting the curve to get 1st and 2nd derivatives.
Your curve, that could as well be modelled by 3 points (at least it looks like that) is "converted to become smooth" and this gives the strange results.
I believe you are better off, re-reading the help file and asking support how to get your desired shape
--
Good luck
Ivar