On 2/14/2011 6:44 PM, shawn wrote: > hiya, > > is there anything for matlab that will solve a 2D/3D reaction- > diffusion problem? I know of pdepe that does 1D, and pdetoolbox that > does 2D, but otherwise, would I have to write my own code? > > thanks! I just looked at pdetool, and it does not look it can do 2D diffusion-reaction pde. What are specs of your problem? domain, boundary conditions? the pde? May be I can you give you one of my matlab functions which solves such problem if it matches what you want. I only have something for unit square grid now. --Nasser

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2/15/2011 4:13:26 AM

Hiya, For my phd thesis, I wrote a custom unstructured finite element (tri / tet) 2D/3D reaction-diffusion solver in matlab. It uses an adams- bashforth / trapezoidal predictor-corrector time integrator with a customised GMRES linear solver (which itself uses matlab's '\' operator), with adaptive time-stepping based on the Gresho and Sani depiction in their CFD books. Hence, this thing handles multiple space and time scales - which I needed for the computational cell biology modeling I performed. Note, there's no Newton solver in it...yet? Anyway, I'm curious if anyone in the matlab community would find this tool useful? I'm considering releasing this into the wild (via sourceforge or mathwokds I'm not sure yet), but that entails writing documentation and probably making it comprehensible to other human beings (oh boy! :). Any feedback from you folks I would greatly appreciate... thanks! shawn "Shawn" wrote in message <bebd6580-2df2-4b61-92af-b857a00ed5db@s9g2000pba.googlegroups.com>... eling I performed. Note, there's no Newton solver in > it...yet? > > Anyway, I'm curious if anyone in the matlab community would find this > tool useful? IMO any good quality is useful. Bruno On Mar 22, 8:24=A0pm, "Bruno Luong" <b.lu...@fogale.findmycountry> wrote: > "Shawn" wrote in message <bebd6580-2df2-4b61-92af-b857a00ed...@s9g2000pba= ..googlegroups.com&g...

This is really meant as the latest in a series I posted over irregular inte= rvals since last summer, in which I'm going to try and explain some of the = tricks used and call out some of the *real* issues that I'd like to tackle = (like reverse "signal demasking" and reverse "layering") These are the demos where some of the tricks are shown off. Bear in mind th= at everything comes from single photos -- no triangulation, no built-in 3D = models, etc. Lighting, coloring, texture, etc. are also inferred from the p= hotos, not built-in or hard-coded. [0] 2D to 3D of a "2D to 3D" video. Trial #2. https://www.youtube.com/watch?v=3DA0mp7hCn5ww We raid someone else's how-to-photoshop photo-to-3D site (it's a cottage in= dustry these days) and turn a snapshot from *it* into a panning 3-D zoom-in= .. It actually zooms inside the video frame. [1] The Beast Stomp Rocks Chicago (literally) https://www.youtube.com/watch?v=3DJdN76XYvvg0 The entire city scape of Chicago rocks in 3D. The cyborg voice in the backg= round morphs from biological to fully robotic. No cityscape model. I left t= he occlusion zones out in the open. [2] Another Pretty Angel Smiles and Flirts https://www.youtube.com/watch?v=3DYKvYir1ldb4 The face in the photo goes from a pout to a flirty smile, while slowly turn= ing and then nods. The photo subject gives ironic twist to the designation = "Artificial Reality" heralded at the end. ...

i want to write Matlab program of gaussian beam (2D or 3D) using helmholtz equation.... if anyone could give the full program, that will help me to do my project work...... thank you :) "Debashis Roy" <deba4u@ymail.com> wrote in message <lhv04i$6sf$1@newscl01ah.mathworks.com>... > i want to write Matlab program of gaussian beam (2D or 3D) using helmholtz equation.... if anyone could give the full program, that will help me to do my project work...... > > thank you :) If anyone could give the full program, they WILL do your project work, not just help. On Tuesday, April 8, 2014 1:30:19 AM UTC+5:30, Debashis Roy wrote: > i want to write Matlab program of gaussian beam (2D or 3D) using helmholtz equation.... if anyone could give the full program, that will help me to do my project work...... > > > > thank you :) ...

Hello,I need some help with 3D reconstruction from image/scene too, so can anybody help me and send me the source code from Prof. Pollefeys? I'm very appreciate! "Beyung Doo Jo" <misonara_@hotmail.co.kr> wrote in message news:iukcbd$cl1$1@newscl01ah.mathworks.com... > Hello,I need some help with 3D reconstruction from image/scene too, so can > anybody help me and send me the source code from Prof. Pollefeys? I'm very > appreciate! Have you tried contacting Professor Pollefeys and ask whether or not they want to share their code with you? If not, then you'll need to implement this function yourself; if you experience problems while doing so, show what you've done and ask a SPECIFIC question and someone may offer some advice. -- Steve Lord slord@mathworks.com To contact Technical Support use the Contact Us link on http://www.mathworks.com ...

Hi Is there any program that can be used to create 3d object and convert it in to Matlab 3d volume matrix? Cheers ...

Hi All, I am trying to plot a 3D grid onto a 3D image in Matlab. May I ask how to do it please? For example, I have got a 3D image with 201x201x201 voxels. I want to plot a 3D grid with 10 voxels spacing on to the image (there will be 21x21x21 cubes to form this 3D grid). I have got the coordinates of the grid in three matrix X, Y, and Z all sized 21x21x21. Then I want to plot both the image and the 3D grid using a Matlab function slidingviewer(...); at FEX. Here is an illustration of the image I want to get. NB: the grid has no need to be regular. http://i54.tinypic.com/2j5hqgh.png [IMG]http://i54.tinypic.com/2j5hqgh.png[/IMG] Thanks very much, Aaronne You might try this function PLOTGRID I make for my own use: function h = plotgrid(ax, xyz, varargin) % function h = plotgrid(ax, xyz, varargin) % Plot the 4D position array xyz(nx,ny,nz,3) in a grid-like plot if isempty(ax) ax = gca(); end hold(ax, 'on'); h = []; for dim=1:3 p = 1:4; p([1 dim]) = [dim 1]; a = permute(xyz, p); m = size(a,1); a = reshape(a, m, [], 3); if m > 1 hd = plot3(ax, a(:,:,1), a(:,:,2), a(:,:,3), '.-', varargin{:}); else hd = plot3(ax, a(:,:,1), a(:,:,2), a(:,:,3), '.', varargin{:}); end h = [h; hd]; end hold(ax, 'off'); end % plotgrid %%%%% Test script [x,y,z] = meshgrid(-2:.2:2,-2:.25:2,-2:.16:2); v = x.*exp(-x.^2-y.^2-z.^2); clf xslice = [-1.2,.8,2]; yslice = 2; zslice =...

Hi, I have 3 columns of data, x (a pressure) and y (a quality at that pressure) of a 'u' shaped curve changing over constant increments of time (z). So I have a x and y curve at certain given times: pressure quality time 1 5 1 2 4 1 3 3 1 4 4 1 5 5 1 1 5 2 2 4 2 3 4 2 3 4 2 4 5 2 1 4 3 2 3 3 3 2 3 4 4 3 5 5 3 I want to show how the curve changes over time by plotting the x vs z, and showing the isolines of the y (quality) at certain ranges (1-2 2-4 4-5). Is there an easy funtion for this purpose? I can't find a function that is suited for this specific goal. Your help would be greatly appreciated, ...

Hi, I have a 3D matrix called timemat(240,5,48) and I want to convert it to 2D timemat(11520,5) meaning that the 48 items of timemat will be listed one under the other in rows.(11520=240x48) Thanks. "Theo" wrote in message <ivhnro$nsu$1@newscl01ah.mathworks.com>... > Hi, > I have a 3D matrix called timemat(240,5,48) and I want to convert it to 2D timemat(11520,5) meaning that the 48 items of timemat will be listed one under the other in rows.(11520=240x48) > > Thanks. This might be what you want, reshape( permute(timemat,[1 3 2]), [] ,5); ...

Hello all, I have a data set, let's call it C, which can be viewed as either an 8x8 matrix or a 64x1 vector.( Basically it is a matrix that looks like: Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 X1 C11 C12 C13 C14 C15 C16 C17 C18 X2 C21 C22 C23 C24 C25 C26 C27 C28 X3 C31 C32 C33 C34 C35 C36 C37 C38 X4 C41 C42 C43 C44 C45 C46 C47 C48 X5 C51 C52 C53 C54 C55 C56 C57 C58 X6 C61 C62 C63 C64 C65 C66 C67 C68 X7 C71 C72 C73 C74 C75 C76 C77 C78 X8 C81 C82 C83 C84 C85 C86 C87 C88 or X1 C11 X2 C12 X3 C13 X4 C14 X5 C15 X6 C16 X7 C17 X8 C18 X1 C21 X2 C22 .... X7 C87 X8 C88 This data can be seen as a function of two independent variables, x and y. Let's say I wanted to fit this data reasonably accurately, ~<10% error. Is there a way to do this in matlab? I have tried to look on the internet for ideas and have seen suggestions for lsqnonlin or lsqcurvefit but these appear to not work how I want them to. I would like something along the lines of polyfit for 3-dimensions where I can specify the order of the polynomial. Thanks, Matt Okay so here is my attempt at using lsqcurvefit, but it's throwing errors and I am too unfamiliar with MatLAB to know why. So my function looks as such: myfun = @(XDATA, a) a(1)+a(2)*XDATA(1)+(a(3)+a(4)*XDATA(1))*(XDATA(2)^-1)+(a(5)+a(6)*XDATA(1))*exp(-XDATA(2)/a(9))+(a(7)+a(8)*XDATA(1))*exp(-(XDATA(2)^2)/a(10)); Where a(1-10) are different coefficients that I am trying to solve for. XDATA looks like a 2x64 ve...

Hi there, Does anyone know of a company in the UK (or indeed software) that can convert 2D autocad Drawings into 3D AutoCad Drawings? We use Navis Works to view 3D drawings sent by clients, but we have very little knowledge of AutoCad 3D. A Client has just sent us 50 or so 2D drawings - We would like them in 3D so that we can use NavisWorks for presentations etc..... Many Thank, Paul. "hutchini" <phutchinson@linacre.co.uk> wrote in message news:1152198425.296341.58950@a14g2000cwb.googlegroups.com... > Hi there, > > Does anyone know of a company in the UK (or indeed software) that can > convert 2D autocad Drawings into 3D AutoCad Drawings? > You want 2D into wireframe (ACAD) so wouldn't you go to someplace like comp.cad.autocad alt.cad.autocad autodesk.autocad.* autodesk.mcad.genius.support autodesk.autocadlt.* ? What does Pro/ENGINEER software have to do with your dilemma? We're not 3D ~ we model solids, big difference, check it out. -- David Janes -- David Janes -- David Janes -- David Janes ...

dear all, How to change matrix dimension from 3D matrix (32x32x32) to 2D matrix (32 x 1024)? Thanks, Asep On 5/23/2012 11:15 PM, Asep wrote: > dear all, > > How to change matrix dimension from 3D matrix (32x32x32) to 2D matrix (32 x 1024)? > > Thanks, > > Asep EDU>> A=rand(32,32,32); EDU>> B=reshape(A,32,1024); EDU>> size(B) ans = 32 1024 ...

Hi, I would like to convert a 2d image to a 3d The one the Stanford and Cornell recently worked on. They have also provide the codes, but I am not sure how should I execute them. Please let me know... You can get the codes from here: http://make3d.cs.cornell.edu/code.html Click under : Make3D v0.1 (Windows) Thanks in advance. Regards, Vijay. "Vijay " <vijay.easwari@gmail.com> wrote in message news:j3tqii$llh$1@newscl01ah.mathworks.com... > Hi, > I would like to convert a 2d image to a 3d The one the Stanford and > Cornell recently worked on. They have also provide the codes, but I am not > sure how should I execute them. Please let me know... > > You can get the codes from here: > > http://make3d.cs.cornell.edu/code.html Have you tried asking the person listed on the Contact page for help getting started? http://make3d.cs.cornell.edu/contact.html -- Steve Lord slord@mathworks.com To contact Technical Support use the Contact Us link on http://www.mathworks.com hi Steve, I mailed them thrice regarding my queries. Its been 6 days now and absolutely no reply from them!! ...

Hi all, I'm pretty new to MATLAB. I just need to know how to reconstruct image using 2D shadows of an object taken at different angles( image taken @ every 10 degree) And also is it possible to get slice info from the reconstructed image. Thanks "Angela" wrote in message <j6cth5$m59$1@newscl01ah.mathworks.com>... > Hi all, I'm pretty new to MATLAB. I just need to know how to reconstruct image using 2D shadows of an object taken at different angles( image taken @ every 10 degree) And also is it possible to get slice info from the reconstructed image. Thanks By projections, you mean radon projections? If so, and if it's a parallel beam 2.5D geometry and if you have the Image Processing Toolbox, then you could apply IRADON slice-by-slice. "Matt J" wrote in message <j6d1ch$6l0$1@newscl01ah.mathworks.com>... > "Angela" wrote in message <j6cth5$m59$1@newscl01ah.mathworks.com>... > > Hi all, I'm pretty new to MATLAB. I just need to know how to reconstruct image using 2D shadows of an object taken at different angles( image taken @ every 10 degree) And also is it possible to get slice info from the reconstructed image. Thanks > > By projections, you mean radon projections? > If so, and if it's a parallel beam 2.5D geometry and if you have the Image Processing Toolbox, then you could apply IRADON slice-by-slice. Projection means i have projected the image to a plane and have taken a set of 2...

I want to implement 2D Barcodes (Datamatrix, QR, PDF417 and Aztec). Are there any scripts already available that might help me for this? Or do I need to start coding from scratch. Any guidance will be deeply appreciated. Thanks I need the same. Could someone help us? ...

Hello, I current produce 3 different plots of probability distributions, where x is plotted versus y. The x axes lengths differ for all 3 plots. The x axis for each plot actually represents a bond of a graph, where the xlim corresponds to the bond length. I'd like to be able to somehow join all 3 plots in a 3D setting, so I can look at how the distributions evolve in time. The 3 x axes would ideally meet at the 0 coordinate. That I believe might involve representing the x axes as lines in 3D. Does anyone have a suggestion? ...

This should be so simple.. but I can't figure it out. I have a 3d array, z, with: 2 parameters x 5 tests x 2 sample sizes I want to take the mean across the 5 tests to get a 2 parameter x 2 sample sizes array. a = mean(z, 2) = [2, 1, 2] - so the 5 tests have been successfully averaged How do I turn the result, a, into a [2 2] array? Appreciate any help, thanks. On 8/11/2011 3:15 AM, Peter wrote: > This should be so simple.. but I can't figure it out. > > I have a 3d array, z, with: 2 parameters x 5 tests x 2 sample sizes > > I want to take the mean across the 5 tests to get a 2 parameter x 2 > sample sizes array. > > a = mean(z, 2) = [2, 1, 2] - so the 5 tests have been successfully averaged > > How do I turn the result, a, into a [2 2] array? .... x=reshape(x,2,2); -- "Peter " <pgillies3@gmail.com> wrote in message <j20333$39b$1@newscl01ah.mathworks.com>... > > a = mean(z, 2) = [2, 1, 2] - so the 5 tests have been successfully averaged > > How do I turn the result, a, into a [2 2] array? =============== squeeze(a) On 8/11/2011 9:15 AM, Matt J wrote: > "Peter " <pgillies3@gmail.com> wrote in message > <j20333$39b$1@newscl01ah.mathworks.com>... >> >> a = mean(z, 2) = [2, 1, 2] - so the 5 tests have been successfully >> averaged >> >> How do I turn the result, a, into a [2 2] array? > =============== > > squeeze(a) ...

Hello everybody ! I came across this video : http://www.youtube.com/watch?v=1OYlqmQFLUI And it is pretty much what I want to do. I have a vehicle model that I built in Simulink, and I want to put it on a virtual road and simulate its motion. How this is possible ? I heard that I may have to use SimMechanics but as I am quite new to Matlab, I don't know all the modules and different things. So what do you recommend me to do (and/or to read) in order to achieve something like what was shown on the video ? Thanks in advance ! :-) "Matt" wrote in message <jo5gm7$j5f$1@newscl01ah.mathworks.com>... > Hello everybody ! > > I came across this video : http://www.youtube.com/watch?v=1OYlqmQFLUI > > And it is pretty much what I want to do. I have a vehicle model that I built in Simulink, and I want to put it on a virtual road and simulate its motion. > > How this is possible ? I heard that I may have to use SimMechanics but as I am quite new to Matlab, I don't know all the modules and different things. > > So what do you recommend me to do (and/or to read) in order to achieve something like what was shown on the video ? > doc plot3 doc surf doc patch Then http://www.mathworks.com/help//matlab/visualize/_f4-22650.html Bruno "Matt " <mathieu.horsky@gmail.com> wrote in message news:jo5gm7$j5f$1@newscl01ah.mathworks.com... > Hello everybody ! > > I came across this video : http://ww...

Hi all, I have a problem on projecting a 3D to 2D dataset. I've plotted the 3D like below: scatter3(x,y,z) But I want to project these points to a 2D space that are shown in a plot with x,y,and z axes, like a surface in 3D space. Is there any idea for how to do this? Thanks in advance. Sophia. Bita Mirshafiee <b.mirshafiee90@gmail.com> wrote in message <10b73180-5648-4597-9dda-aabb5ca1c1e7@f33g2000yqh.googlegroups.com>... > Hi all, > > I have a problem on projecting a 3D to 2D dataset. I've plotted the 3D > like below: > > scatter3(x,y,z) > > But I want to project these points to a 2D space that are shown in a > plot with x,y,and z axes, like a surface in 3D space. > Is there any idea for how to do this? =============== If the 2D surface is curved/non-planar, you may need FMINCON in the Optimization Toolbox. I.e., for each fixed point v=(x,y,z) you would solve the constrained minimization problem min(norm(u-v)) s.t. u belongs to the surface ...

Right now I have a bunch (125) of 2D slices (254x254) from a CT scan. I bundled those in a cube of 254x254x125. I would like to plot this as a 3D image. Afterwards I have to find certain 3D shapes within that image. I thought of using some sort of correlation function. How can I achieve this? "Akyro" wrote in message <iovegs$gtd$1@fred.mathworks.com>... > Right now I have a bunch (125) of 2D slices (254x254) from a CT scan. I bundled those in a cube of 254x254x125. I would like to plot this as a 3D image. > > Afterwards I have to find certain 3D shapes within that image. I thought of using some sort of correlation function. > > How can I achieve this? In addition: I have tried to use the function "slice", but if i want to display the whole 3D model, there is only a solid white or black block to be seen since the slices have no transparency. Each slice is predominantly white with only a few black dots, so if the white was transparent, the figure could be seen. On Apr 23, 5:43=A0pm, "Akyro " <vidar5...@gmail.com> wrote: > "Akyro" wrote in message <iovegs$gt...@fred.mathworks.com>... > > Right now I have a bunch (125) of 2D slices (254x254) from a CT scan. I= bundled those in a cube of 254x254x125. I would like to plot this as a 3D = image. > > > Afterwards I have to find certain 3D shapes within that image. I though= t of using some sort of correlation function. > > >...

Does anybody know what the pros/cons are of different matlab solvers? Like: iterative solver ( Jacobi, Gauss-Seidel, SOR ) and direct solvers? ...

Hallo evrybody, I have two VRML file (3d colored point cloud) and I want to align these models. i don't if there are an easy way to ensure this alignment with Matlab. Thx for your reply ...

Hello! I am trying to make a 3D plot of some variables: x, y and t (all real numbers). My variables are: +++++++++++++++++++++++++ Variable Size per "whos" command +++++++++++++++++++++++++ x [1 x 2000] y [1 x 2000] t [506 x 2000] I have a problem when trying to use the contour3 command. I do realize that the dimensions are different with the matrices. How can I make a 3D contour plot of the given data? Any help is greatly appreciated. Adam On Sep 26, 8:40=A0am, "adam Smith" <f...@live.com> wrote: > Hello! > > I am trying to make a 3D plot of some variables: x, y and t (all real num= bers). > > My variables are: > +++++++++++++++++++++++++ > Variable =A0 =A0Size per "whos" command > +++++++++++++++++++++++++ > x =A0 =A0 =A0 =A0 =A0 =A0 [1 x 2000] =A0 > y =A0 =A0 =A0 =A0 =A0 =A0 [1 x 2000] =A0 > t =A0 =A0 =A0 =A0 =A0 =A0 [506 x 2000] > > =A0I have a problem when trying to use the contour3 command. I do realize= that the dimensions are different with the matrices. How can I make a 3D c= ontour plot of the given data? =A0 > > Any help is greatly appreciated. > Adam Not enough information............... Do the 2000 data points of x and y form a rectangular grid? If you type: plot(x,y,'bo') what do you see? And when you finally get a 3D contour plot, what do you expect to see? In what way will it be different from a 2D c...

I have some 3D data that I need to import into Matlab. I can not figure out how to import it, does anyone know? I do not think a simple IMread will work, or am I wrong? Finally is there a way to upload a video clip into matlab? I have some data as a movie I would like to upload, but it is not as important as the 3-D pictures being uploaded. Thanks. Mitchell "Mitchell Blenden" wrote in message <is86nh$aoo$1@newscl01ah.mathworks.com>... > I have some 3D data that I need to import into Matlab. I can not figure out how to import it, does anyone know? I do not think a simple IMread will work, or am I wrong? Finally is there a way to upload a video clip into matlab? I have some data as a movie I would like to upload, but it is not as important as the 3-D pictures being uploaded. Thanks. > Mitchell Hi Mitchell, What format is your 3D data in? imread() may very well work if when you say 3D data, you are talking about a truecolor image. I think you need to tell us a bit more. There are multiple ways to read video into MATLAB depending on which toolboxes you have installed. Look at >>doc VideoReader As one example. If you have the Computer Vision Toolbox, you may want to look at the System object: vision.VideoFileReader Wayne ...

dear all, How to change matrix dimension from 3D matrix (32x32x32) to 2D matrix (32 x 1024)? Thanks, Asep On 5/24/2012 2:21 AM, Asep wrote: > dear all, > > How to change matrix dimension from 3D matrix (32x32x32) to 2D matrix (32 x 1024)? > > Thanks, > > Asep EDU>> A=rand(32,32,32); EDU>> B=reshape(A,32,1024); EDU>> size(B) ans = 32 1024 ...

The Turing, or reaction-diffusion (RD), model is one of the best-known theoretical models used to explain self-regulated pattern formation in ...

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