octave

I would like to add two vectors with different lengths in Matlab or Octave. E.g. aa = [1 2 3 4]; bb = [100 100]; Which should result in a vector cc containing cc = [101 102 3 4] Can anyone figure out how to do this? Update: This is the code I ended up with for the signals that I then later convert to grey scale images. load train; t = y; load chirp; c = y; tc = c + [t; zeros(length(c) - length(t),1)]; plot(1:length(tc),tc) Thank you very much to you all =) This doesn't make any sense mathematically, but if you insist, you can do this: cc = aa + [bb zeros(1,2)]; For the 1-D case dealing with a

I'm using Octave and R to compute SVD using a simple matrix and getting two different answers! The code is listed below: R > a<-matrix(c(1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,1,1,1), 9, 4) > a [,1] [,2] [,3] [,4] [1,] 1 1 0 0 [2,] 1 1 0 0 [3,] 1 1 0 0 [4,] 1 0 1 0 [5,] 1 0 1 0 [6,] 1 0 1 0 [7,] 1 0 0 1 [8,] 1 0 0 1 [9,] 1 0 0 1 > a.svd <- svd(a) > a.svd$d [1] 3.464102e+00 1.732051e+00 1.732051e+00 1.922963e-16 > a.svd$u [,1] [,2] [,3] [,4] [1,] -0.3333333 0.4714045 -1.741269e-16 7.760882e-01 [2,] -0.3333333 0.4714045 -3.692621e-16 -1.683504e-01 [3,] -0.3333333 0

I installed latest Octave on Ubuntu 14.04 machine. However, when I tried to run imread command, it showed the following error message: octave:12> imread('newfile.png') error: imread: invalid image file: /usr/lib/x86_64-linux-gnu/octave/3.8.1/oct/x86_64-pc-linux-gnu/__magick_read__.oct: failed to load: /usr/lib/x86_64-linux-gnu/octave/3.8.1/oct/x86_64-pc-linux-gnu/__magick_read__.oct: undefined symbol: _ZN6Magick5ColorC1Ehhh error: called from: error: /usr/share/octave/3.8.1/m/image/private/__imread__.m at line 181, column 7 error: /usr/share/octave/3.8.1/m/image/private/imageIO.m at line 66,

One of the first things one learns about programming efficiently in MATLAB is to avoid dynamically resizing arrays. The standard example is as follows. N = 1000; % Method 0: Bad clear a for i=1:N a(i) = cos(i); end % Method 1: Better clear a; a = zeros(N,1); for i=1:N a(i) = cos(i) end The 'Bad' variant here requires O( N ^2) time to run, as it must allocate a new array and copy the old values at each iteration of the loop. My own preferred practice when debugging is to allocate an array with NaN , harder to confuse with a valid value than 0 . % Method 2: Easier to Debug clear a; a = NaN(N,1);

In MatLab, you can declare symbols pretty easily: syms a,b mat = [a,b] I'm getting an error, however, when I try to replicate this in Octave. This is the code I'm using: > symbols > a = sym("a") a = a > b = sym("b") b = b > mat = [a,b] error: octave_base_value::resize (): wrong type argument `ex' error: octave_base_value::resize (): wrong type argument `<unknown type>' octave-3.2.3.exe:4:C:\Octave\3.2.3_gcc-4.4.0\bin How do you declare a symbolic matrix in octave? Would this help ? It looks like you might need the symbolic toolbox package , reference here . Dave Goldsmith If you don't already

I'm using Octave to write a script that plots a function at different time periods. I was hoping to create an animation of the plots in order to see the changes through time. Is there a way to do this so to possibly save each plot for each time in some way that each plot can be combined to create this animation? Thanks in advance for the advise! This creates an animated gif data=rand(100,100,20); %100 by 100 and 20 frames %data go from 0 to 1, so lets convert to 8 bit unsigned integers for saving data=data*2^8; data=uint8(data); %Write the first frame to a file named animGif.gif imwrite(data(:

my target is to have a plot that shows Stochastic oscillator on forex market, and in order to validate which parameter is the best one to setup it, I would use a slider to modify it and show updated result on plot. I have my historical data, for a defined pair (let say AUDUSD) and after loading it, I calculate Stocastic oscillator: function [stoch, fk, dk] = stochastic(n, k, d) X=csvread("AUDUSD_2017.csv"); C=X(2:length(X),5); L=X(2:length(X),4); H=X(2:length(X),3); O=X(2:length(X),2); for m=n:length(C)-n stoch(m)=((C(m)-min(L(m-n+1:m)))/(max(H(m-n+1:m))-min(L(m-n+1:m))))*100; endfor for m=n