Search Results

Search found 9638 results on 386 pages for 'matlab engine'.

Page 54/386 | < Previous Page | 50 51 52 53 54 55 56 57 58 59 60 61  | Next Page >

  • How do I translate this Matlab bsxfun call to R?

    - by claytontstanley
    I would also (fingers crossed) like the solution to work with R Sparse Matrices in the Matrix package. >> A = [1,2,3,4,5] A = 1 2 3 4 5 >> B = [1;2;3;4;5] B = 1 2 3 4 5 >> bsxfun(@times, A, B) ans = 1 2 3 4 5 2 4 6 8 10 3 6 9 12 15 4 8 12 16 20 5 10 15 20 25 >> EDIT: I would like to do a matrix multiplication of these sparse vectors, and return a sparse array: > class(NRowSums) [1] "dsparseVector" attr(,"package") [1] "Matrix" > class(NColSums) [1] "dsparseVector" attr(,"package") [1] "Matrix" > NRowSums * NColSums (I think) w/o using a non-sparse variable to temporarily store data.

    Read the article

  • High volume SVM (machine learning) system

    - by flyingcrab
    I working on a possible machine learning project that would be expected to do high speed computations for machine learning using SVM (support vector machines) and possibly some ANN. I'm resonably comfortable working on matlab with these, but primarly in small datasets, just for experimentation. I'm wondering if this matlab based approach will scale? or should i be looking into something else? C++ / gpu based computing? java wrapping of the matlab code and pushing it onto app engine? Incidentally, there seems to be a lot fo literature on GPUs, but not much on how useful they are on machine learning applications using matlab, & the cheapest CUDA enlabled GPU money can buy? is it even worth the trouble?

    Read the article

  • Psychology researcher wants to learn new language

    - by user273347
    I'm currently considering R, matlab, or python, but I'm open to other options. Could you help me pick the best language for my needs? Here are the criteria I have in mind (not in order): Simple to learn. I don't really have a lot of free time, so I'm looking for something that isn't extremely complicated and/or difficult to pick up. I know some C, FWIW. Good for statistics/psychometrics. I do a ton of statistics and psychometrics analysis. A lot of it is basic stuff that I can do with SPSS, but I'd like to play around with the more advanced stuff too (bootstrapping, genetic programming, data mining, neural nets, modeling, etc). I'm looking for a language/environment that can help me run my simpler analyses faster and give me more options than a canned stat package like SPSS. If it can even make tables for me, then it'll be perfect. I also do a fair bit of experimental psychology. I use a canned experiment "programming" software (SuperLab) to make most of my experiments, but I want to be able to program executable programs that I can run on any computer and that can compile the data from the experiments in a spreadsheet. I know python has psychopy and pyepl and matlab has psychtoolbox, but I don't know which one is best. If R had something like this, I'd probably be sold on R already. I'm looking for something regularly used in academe and industry. Everybody else here (including myself, so far) uses canned stat and experiment programming software. One of the reasons I'm trying to learn a programming language is so that I can keep up when I move to another lab. Looking forward to your comments and suggestions. Thank you all for your kind and informative replies. I appreciate it. It's still a tough choice because of so many strong arguments for each language. Python - Thinking about it, I've forgotten so much about C already (I don't even remember what to do with an array) that it might be better for me to start from scratch with a simple program that does what it's supposed to do. It looks like it can do most of the things I'll need it to do, though not as cleanly as R and MATLAB. R - I'm really liking what I'm reading about R. The packages are perfect for my statistical work now. Given the purpose of R, I don't think it's suited to building psychological experiments though. To clarify, what I mean is making a program that presents visual and auditory stimuli to my specifications (hundreds of them in a preset and/or randomized sequence) and records the response data gathered from participants. MATLAB - It's awesome that cognitive and neuro folk are recommending MATLAB, because I'm preparing for the big leap from social and personality psychology to cognitive neuro. The problem is the Uni where I work doesn't have MATLAB licenses (and 3750 GBP for a compiler license is not an option for me haha). Octave looks like a good alternative. PsychToolbox is compatible with Octave, thankfully. SQL - Thanks for the tip. I'll explore that option, too. Python will be the least backbreaking and most useful in the short term. R is well suited to my current work. MATLAB is well suited to my prospective work. It's a tough call, but I think I am now equipped to make a more well-informed decision about where to go next. Thanks again!

    Read the article

  • How do I draw a texture-mapped triangle in MATLAB?

    - by Petter
    I have a triangle in (u,v) coordinates in an image. I would like to draw this triangle at 3D coordinates (X,Y,Z) texture-mapped with the triangle in the image. Here, u,v,X,Y,Z are all vectors with three elements representing the three corners of the triangle. I have a very ugly, slow and unsatisfactory solution in which I (1) extract a rectangular part of the image, (2) transform it to 3D space with the transformation defined by the three points, (3) draw it with surface, and (4) finally masking out everything that is not part of the triangle with AlphaData. Surely there must be an easier way of doing this?

    Read the article

  • How do I make matlab legends match the colour of the graphs?

    - by Alex Gosselin
    Here is the code I used: x = linspace(0,2); e = exp(1); lin = e; quad = e-e.*x.*x/2; cub = e-e.*x.*x/2; quart = e-e.*x.*x/2+e.*x.*x.*x.*x/24; act = e.^cos(x); mplot = plot(x,act,x,lin,x,quad,x,cub,x,quart); legend('actual','linear','quadratic','cubic','quartic') This produces a legend matching the right colors to actual and linear, then after that it seems to skip over red on the graph, but not on the legend, i.e. the legend says quadratic should be red, but the graph shows it as green, the legend says cubic should be green, but the graph shows it as purple etc. Any help is appreciated.

    Read the article

  • How to strink matrix using array mask in Matlab?

    - by Pyrolistical
    This seems to be a very common problem of mine. data = [1 2 3; 4 5 6]; mask = [true false true]; mask = repmat(mask, 2, 1); data(mask) ==> [1; 4; 3; 6] What I wanted was [1 3; 4 6] Yes I can just reshape it to the right size, but that seems the wrong way to do it. Is there a better way? Why doesn't data(mask) return a matrix when it is actually rectangular? I understand in the general case it may not be, but in my case since my original mask is an array it always will be.

    Read the article

  • Deterministic Annealing Code

    - by wade
    I would like to find an open source example of a code for deterministic annealing. It can be in almost any language: C, C++, MatLab/Octave, Fortran. I have already found a MatLab code for simulated annealing, so MatLab would be best. Here is a paper that describes the algorithm: http://www.google.com/url?sa=t&source=web&ct=res&cd=1&ved=0CB8QFjAA&url=http%3A%2F%2Fvandamteaching.googlepages.com%2FABriefIntroductionToDeterministicAnn.pdf&ei=DiLiS8qZFI7AMozB1JED&usg=AFQjCNHLps7HRWXLNN5rAX5aJ5BsJbcHuQ&sig2=YSokUTOs0UszAFZ9TDiJgQ

    Read the article

  • How to generate a lower frequency version of a signal in Matlab?

    - by estourodepilha.com
    With a sine input, I tried to modify it's frequency cutting some lower frequencies in the spectrum, shifting the main frequency towards zero. As the signal is not fftshifted I tried to do that by eliminating some samples at the begin and at the end of the fft vector: interval = 1; samplingFrequency = 44100; signalFrequency = 440; sampleDuration = 1 / samplingFrequency; timespan = 1 : sampleDuration : (1 + interval); original = sin(2 * pi * signalFrequency * timespan); fourierTransform = fft(original); frequencyCut = 10; %% Hertz frequencyCut = floor(frequencyCut * (length(pattern) / samplingFrequency) / 4); %% Samples maxFrequency = length(fourierTransform) - (2 * frequencyCut); signal = ifft(fourierTransform(frequencyCut + 1:maxFrequency), 'symmetric'); But it didn't work as expected. I also tried to remove the center part of the spectrum, but it wielded a higher frequency sine wave too. How to make it right?

    Read the article

  • How can I make XOR work for logical matrix in MATLAB?

    - by Runner
    >> XOR(X,X) ??? Undefined function or method 'XOR' for input arguments of type 'logical'. Why XOR can't be used for logical matrix? And I tried a more simple example: >> A=[1 0;1 0]; >> B=[1 1;0 0]; >> XOR(A,B) ??? Undefined function or method 'XOR' for input arguments of type 'double'. How can I properly use XOR?

    Read the article

  • Strange Matlab error: "??? Subscript indices must either be real positive integers or logicals"

    - by Roee Adler
    I have a function func that returns a vector a. I usually plot a and then perform further analysis on it. I have a certain scenario when once I try to plot a, I get a "??? Subscript indices must either be real positive integers or logicals" error. Take a look at the following piece of code to see the vector's behavior: K>> a a = 5.7047 6.3529 6.4826 5.5750 4.1488 5.8343 5.3157 5.4454 K>> plot(a) ??? Subscript indices must either be real positive integers or logicals. K>> for i=1:length(a); b(i) = a(i); end; K>> b b = 5.7047 6.3529 6.4826 5.5750 4.1488 5.8343 5.3157 5.4454 K>> plot(b) ??? Subscript indices must either be real positive integers or logicals. The scenario where this happens is when I call function func from within another function (call it outer_func), and return the result directly as outer_func's result. When debugging inside outer_func, I can plot a properly, but outside the scope of outer_func, its result has the above behavior. What can cause this? Where do I start from?

    Read the article

  • Dimension Mismatch MatLab; cant figure out why it is mismatching

    - by Abid
    I think it may be a syntax issue, here is the code. load ([ 'C:\Users\Abid\Desktop\Inquiry Runs\dtS' ]) dtS((dtS==0))=nan; for j=2:9; maxS=max(dtS(j,:)); minS=min(dtS(j,:)); maxval(j,:)=dtS((dtS>(maxS-.1*maxS))); minval(j,:)=dtS((dtS<(minS+.1*minS))); avmax(j)=mean(maxval(j,:)); avmin(j)=mean(minval(j,:)); avs(j,:)=[avmax(j) avmin(j)] end So I know the the row matrices are different sizes every loop. For example maxval(j,:) will change depending one row it is looking through for certain values. I did this manually and I see that on the first loop the matrices are size (1,1), however, if I set the loop to run for only j=2, the row length is 13. Usually if a matrix is changing size on the loop, I only get a warning, but this time I think it is due to a reason I don't understand.

    Read the article

  • How to mask part of an image in matlab ?

    - by ZaZu
    Hey guys, I would like to know how to mask part of an image that is in BLACK & WHITE ? I got an object that needs to be edge detected, but I have other white interfering objects in the background that are below the target objet ... I would like to mask the entire lower part of an image to black, how can I do that ? Thanks !!

    Read the article

  • Is there anything like deal() for normal MATLAB arrays?

    - by jjkparker
    When dealing with cell arrays, I can use the deal() function to assign cells to output variables, such as: [a, b, c] = deal(myCell{:}); or just: [a, b, c] = myCell{:}; I would like to do the same thing for a simple array, such as: myArray = [1, 2, 3]; [a, b, c] = deal(myArray(:)); But this doesn't work. What's the alternative?

    Read the article

  • How to make disconnected closed curves connected by adding a shortest path using MATLAB?

    - by user198729
    bwlabel can be used to get disconnected objects in an image: [L Ne] = bwlabel(image); I want to make the objects(But my target is only the contours(closed curve) of these objects) connected by adding a shortest path where necessary. How do I approach this? UPDATE Or how to dilate the closed curves so that they get connected? How to calculate the shortest path between two disconnected closed curves?

    Read the article

< Previous Page | 50 51 52 53 54 55 56 57 58 59 60 61  | Next Page >