In newer versions of MATLAB (R2015a and later) the easiest way to do this is using the repelem function: B = repelem(A, 2, 2); For older versions, a short alternative to the other (largely) indexing-based solutions is to use the functions kron and ones: >> A = [2 6; 8 4]; >> B = kron(A, … Read more
You could also do this completely vectorized by using mat2cell, cellfun, then cell2mat. Assuming our matrix is stored in A, try: numBlocks = size(A,1) / 3; B = mat2cell(A, 3*ones(1,numBlocks), 3); C = cellfun(@(x) x – x([1 1 1], :), B, ‘UniformOutput’, false); D = cell2mat(C); %//Output The first line figures out how many 3 … Read more
You need to use interp1 with ‘linear’ interpolation method: >> v = [1 2 3 4 10]; >> newNum = 13; % new number of elements in the “buffed” vector >> iv = interp1( linspace(0,1,numel(v)), v, linspace(0,1,newNum) ) iv = 1.0000 1.3333 1.6667 2.0000 2.3333 2.6667 3.0000 3.3333 3.6667 4.0000 6.0000 8.0000 10.0000
The complete rotation matrices are derived and given at https://sites.google.com/site/glennmurray/glenn-murray-ph-d/rotation-matrices-and-formulas/rotation-about-an-arbitrary-axis-in-3-dimensions. From the paper: 5.2 The simplified matrix for rotations about the origin Note this assumes that (u, v, w) is a direction vector for the axis of rotation and that u^2 + v^2 + w^2 = 1. If you have a point (x, y, z) … Read more
You can take a look at the code here. I think the function is similar to what you are trying to solve. The function extracts an arbitrary plane from a volume given the size of the plane, the center point of the plane, and the plane normal, i.e. [A,B,C]. It also outputs the volumetric index … Read more
How about this? (KISS solution) void LoadCities() { int x, y; ifstream in(“Cities.txt”); if (!in) { cout << “Cannot open file.\n”; return; } for (y = 0; y < 15; y++) { for (x = 0; x < 15; x++) { in >> distances[x][y]; } } in.close(); } Works for me. Might not be that … Read more
The issue is that when you’re assigning values back to w1 from w2 you aren’t actually passing the values from w1 to w2, but rather you are actually pointing the two variables at the same object. The issue you are having w1 = np.array([1,2,3]) w2 = w1 w2[0] = 3 print(w2) # [3 2 3] … Read more
To go the opposite direction which is what I needed: void printxy(int index) { int y = (int)((-1+sqrt(8*index+1))/2); int x = index – y*(y+1)/2; }
public static double[][] transposeMatrix(double [][] m){ double[][] temp = new double[m[0].length][m.length]; for (int i = 0; i < m.length; i++) for (int j = 0; j < m[0].length; j++) temp[j][i] = m[i][j]; return temp; }