Comments on: Advanced MATLAB: Surface plot of nonuniform data http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/ <a href="http://www.mathworks.com/matlabcentral/fileexchange/loadAuthor.do?objectId=969735&objectType=author">Bob</a>, <a href="http://www.mathworks.com/matlabcentral/fileexchange/loadAuthor.do?objectId=1093599&objectType=author">Brett</a> & <a href="http://www.mathworks.com/matlabcentral/fileexchange/loadAuthor.do?objectId=1094142&objectType=author">Jiro</a> share favorite user-contributed submissions from the File Exchange. Sun, 22 Nov 2009 23:13:01 +0000 http://wordpress.org/?v=2.3.1 By: Doug http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-13298 Doug Wed, 11 Nov 2009 20:16:21 +0000 http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-13298 @Teja, I think this will work: http://www.mathworks.com/access/helpdesk/help/techdoc/ref/delaunaytriclass.html Doug @Teja,

I think this will work:

http://www.mathworks.com/access/helpdesk/help/techdoc/ref/delaunaytriclass.html

Doug

]]> By: Teja http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-13296 Teja Wed, 11 Nov 2009 13:17:10 +0000 http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-13296 Dear Doug Is there anyway to plot a surface from nonuniform data without meshgrid and griddata? Basically i have topographic information, where the altitude(z) at each x and y is known. I do not want any interpolation in between. x and y do not form a rectangular grid but are closely spaced. Thanks Dear Doug
Is there anyway to plot a surface from nonuniform data without meshgrid and griddata? Basically i have topographic information, where the altitude(z) at each x and y is known.
I do not want any interpolation in between. x and y do not form a rectangular grid but are closely spaced.
Thanks

]]> By: Doug http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-13291 Doug Tue, 10 Nov 2009 15:49:10 +0000 http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-13291 @Daniel, I think you would be well served to look at the series about volume visualization. It starts here: http://blogs.mathworks.com/videos/2009/10/23/basics-volume-visualization-19-defining-scalar-and-vector-fields/ The one about isosurfaces will be posted today or tomorrow (11/10/2009). That is very likely the function you seek. Doug @Daniel,

I think you would be well served to look at the series about volume visualization. It starts here:

http://blogs.mathworks.com/videos/2009/10/23/basics-volume-visualization-19-defining-scalar-and-vector-fields/

The one about isosurfaces will be posted today or tomorrow (11/10/2009). That is very likely the function you seek.

Doug

]]> By: Daniel http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-13290 Daniel Sun, 08 Nov 2009 21:18:42 +0000 http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-13290 Hi Doug Thanks for these videos, they have really helped me alot. I am currently looking to create a surface plot (non uniform data) but I would like to represent it in the z-axis. To explain myself better: If you think of various layers of semi circles made up of dots, and as you move 'up', the number of dots are increasing, so it ends up looking like a funnel. Now the code you presented here creates a surface for each circle (ie. for each layer), but now I want to create a surface joining the layers. I hope I have explained myself adequately. Thanks again and I would really appreciate your input. Kind Regards Hi Doug

Thanks for these videos, they have really helped me alot. I am currently looking to create a surface plot (non uniform data) but I would like to represent it in the z-axis. To explain myself better:

If you think of various layers of semi circles made up of dots, and as you move ‘up’, the number of dots are increasing, so it ends up looking like a funnel. Now the code you presented here creates a surface for each circle (ie. for each layer), but now I want to create a surface joining the layers. I hope I have explained myself adequately. Thanks again and I would really appreciate your input.

Kind Regards

]]> By: Doug http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-11364 Doug Tue, 27 May 2008 17:30:30 +0000 http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-11364 Venkat, I am not sure that I understand the question. If you have x,y,z triples, you just plot them. Are you trying to fit a polynomial to them? That would imply a two dimensional dataset. Are you trying to fit some kind of a surface to the data? You might be best off looking here: http://blogs.mathworks.com/pick/how-to-get-help/ It shows how to ask for help at the bottom. Doug Venkat,

I am not sure that I understand the question. If you have x,y,z triples, you just plot them. Are you trying to fit a polynomial to them? That would imply a two dimensional dataset. Are you trying to fit some kind of a surface to the data?

You might be best off looking here:

http://blogs.mathworks.com/pick/how-to-get-help/

It shows how to ask for help at the bottom.

Doug

]]> By: venkat http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-11286 venkat Sun, 18 May 2008 07:47:33 +0000 http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-11286 I have multiple [x,y,z] matrices of my data with which i want to plot the surface using a 7th order polynomial, how can I do that?? I have multiple [x,y,z] matrices of my data with which i want to plot the surface using a 7th order polynomial, how can I do that??

]]> By: Jim http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-10441 Jim Thu, 03 Apr 2008 06:33:30 +0000 http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-10441 I have three column data (time,height,collection) supposedly x,y,z data. I want to plot it and get the equation. How can I do that with Matlab. eg data: x - y - z 1 - 1 - 130 2 - 1 - 130 3 - 1 - 130 4 - 1 - 130 7 - 2 - 130 10 - 2 - 130 16 - 2 - 130 25 - 2 - 130 40 - 2 - 130 63 - 3 - 130 100 - 3 - 130 160 - 3 - 130 250 - 3 - 130 300 - 3 - 130 400 - 3 - 130 500 - 3 - 130 1 - 3 - 260 2 - 3 - 260 3 - 3 - 260 4 - 3 - 260 7 - 3 - 260 10 - 3 - 260 16 - 4 - 260 25 - 4 - 260 40 - 4 - 260 63 - 6 - 260 100 - 8 - 260 160 - 10 - 260 250 - 11 - 260 300 - 11 - 260 400 - 11 - 260 500 - 11 - 260 1 - 4 - 390 2 - 5 - 390 3 - 5 - 390 4 - 5 - 390 7 - 6 - 390 10 - 7 - 390 16 - 8 - 390 25 - 10 - 390 40 - 12 - 390 63 - 14 - 390 100 - 15 - 390 160 - 19 - 390 250 - 22 - 390 300 - 26 - 390 400 - 30 - 390 500 - 30 - 390 1 - 4 - 650 2 - 5 - 650 3 - 5 - 650 4 - 5 - 650 7 - 5 - 650 10 - 7 - 650 16 - 8 - 650 25 - 9 - 650 40 - 12 - 650 63 - 14 - 650 100 - 18 - 650 160 - 22 - 650 250 - 27 - 650 300 - 27 - 650 400 - 36 - 650 500 - 40 - 650 1 - 2 - 910 2 - 2 - 910 3 - 2 - 910 4 - 3 - 910 7 - 5 - 910 10 - 5 - 910 16 - 7 - 910 25 - 9 - 910 40 - 15 - 910 63 - 20 - 910 100 - 24 - 910 160 - 32 - 910 250 - 38 - 910 300 - 41 - 910 400 - 46 - 910 500 - 49 - 910 I have three column data (time,height,collection) supposedly x,y,z data. I want to plot it and get the equation. How can I do that with Matlab.
eg data:
x - y - z
1 - 1 - 130
2 - 1 - 130
3 - 1 - 130
4 - 1 - 130
7 - 2 - 130
10 - 2 - 130
16 - 2 - 130
25 - 2 - 130
40 - 2 - 130
63 - 3 - 130
100 - 3 - 130
160 - 3 - 130
250 - 3 - 130
300 - 3 - 130
400 - 3 - 130
500 - 3 - 130
1 - 3 - 260
2 - 3 - 260
3 - 3 - 260
4 - 3 - 260
7 - 3 - 260
10 - 3 - 260
16 - 4 - 260
25 - 4 - 260
40 - 4 - 260
63 - 6 - 260
100 - 8 - 260
160 - 10 - 260
250 - 11 - 260
300 - 11 - 260
400 - 11 - 260
500 - 11 - 260
1 - 4 - 390
2 - 5 - 390
3 - 5 - 390
4 - 5 - 390
7 - 6 - 390
10 - 7 - 390
16 - 8 - 390
25 - 10 - 390
40 - 12 - 390
63 - 14 - 390
100 - 15 - 390
160 - 19 - 390
250 - 22 - 390
300 - 26 - 390
400 - 30 - 390
500 - 30 - 390
1 - 4 - 650
2 - 5 - 650
3 - 5 - 650
4 - 5 - 650
7 - 5 - 650
10 - 7 - 650
16 - 8 - 650
25 - 9 - 650
40 - 12 - 650
63 - 14 - 650
100 - 18 - 650
160 - 22 - 650
250 - 27 - 650
300 - 27 - 650
400 - 36 - 650
500 - 40 - 650
1 - 2 - 910
2 - 2 - 910
3 - 2 - 910
4 - 3 - 910
7 - 5 - 910
10 - 5 - 910
16 - 7 - 910
25 - 9 - 910
40 - 15 - 910
63 - 20 - 910
100 - 24 - 910
160 - 32 - 910
250 - 38 - 910
300 - 41 - 910
400 - 46 - 910
500 - 49 - 910

]]> By: Doug http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-10428 Doug Wed, 02 Apr 2008 15:37:25 +0000 http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-10428 Els, There is no built in function to do this, but knowing the X,Y,Z of each point in the mesh, you should be able to calculate the area of each four point patch. From there, summing should be easy to know the whole area. Doug Els,

There is no built in function to do this, but knowing the X,Y,Z of each point in the mesh, you should be able to calculate the area of each four point patch. From there, summing should be easy to know the whole area.

Doug

]]> By: Els http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-10417 Els Wed, 02 Apr 2008 09:35:51 +0000 http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-10417 Dear Doug, This info about making a surface plot was very usefull for me. In stead of the formule that you used to produce some points, I used 4 XYZ-coordinates that result in an surface in 3D. Is there an easy way to calculate the surface area of this created object? Best regards, Els Dear Doug,

This info about making a surface plot was very usefull for me. In stead of the formule that you used to produce some points, I used 4 XYZ-coordinates that result in an surface in 3D. Is there an easy way to calculate the surface area of this created object?

Best regards,
Els

]]> By: Doug http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-5997 Doug Mon, 19 Nov 2007 13:22:18 +0000 http://blogs.mathworks.com/pick/2007/11/02/advanced-matlab-surface-plot-of-nonuniform-data/#comment-5997 Greg pointed me to this solution he wrote a while back that might be of interest also: Tech Note 1212 - Using MESHGRID and GRIDDATA to Fit Vector Data and Plot Unevenly Spaced Data http://www.mathworks.com/support/tech-notes/1200/1212.html Greg pointed me to this solution he wrote a while back that might be of interest also:

Tech Note 1212 - Using MESHGRID and GRIDDATA to Fit Vector Data and Plot Unevenly Spaced Data http://www.mathworks.com/support/tech-notes/1200/1212.html

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