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You are not logged in. #2 20121226 04:50:16
Re: GramSchmidt matrix factorization in C++Hi; Code:#include <iostream> #include <glm/glm.hpp> glm::vec3 sum_over_e(glm::vec3* e, glm::vec3* e_prime, int& i) { int k = 0; glm::vec3 result; while (k < i1) { float e_prime_k_squared = glm::dot(e_prime[k], e_prime[k]); result += ((glm::dot(e[i], e_prime[k]) / e_prime_k_squared) * e_prime[k]); k++; } return result; } int main(int argc, char** argv) { int n = 3; // number of vectors we're working with glm::vec3 e[] = { glm::vec3(sqrt(2)/2, sqrt(2)/2, 0), glm::vec3(1, 1, 1), glm::vec3(0, 2, 2) }; glm::vec3 e_prime[n]; e_prime[0] = e[0]; // step A int i = 0; // step B do // step C { e_prime[i] = e[i]  sum_over_e(e, e_prime, i); i++; // step D } while (i < n); for (int loop_count = 0; loop_count < n; loop_count++) { std::cout << "Vector e_prime_" << loop_count+1 << ": < " << e_prime[loop_count].x << ", " << e_prime[loop_count].y << ", " << e_prime[loop_count].z << " >" << std::endl; } return 0; That is supposed to orthogonalize those three vectors using Gram Schmidt. I have not tried it but it is supposed to work. In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #3 20130107 22:21:28
Re: GramSchmidt matrix factorization in C++I found a solution: Code:int k, i, j; for (k=0; k<3; k++) { r[k][k]=0; // equivalent to sum = 0 for (i=0; i<3; i++) r[k][k] = r[k][k] + a[i][k] * a[i][k]; // rkk = sqr(a0k) + sqr(a1k) + sqr(a2k) r[k][k] = sqrt(r[k][k]); // a for (i=0; i<3; i++) q[i][k] = a[i][k]/r[k][k]; for(j=k+1; j<3; j++) { r[k][j]=0; for(i=0; i<3; i++) r[k][j] += q[i][k] * a[i][j]; for (i=0; i<3; i++) a[i][j] = a[i][j]  r[k][j]*q[i][k]; } I have tested this and it's working good. Code:int k, i, j; #pragma omp parallel for private (k, i, j) shared (a, q, r) // ........ but it doesn't work correctly. I noticed that the problematic fragment is: Code:for (i=0; i<3; i++) q[i][k] = a[i][k]/r[k][k]; but I don't know why it makes a problem... #4 20130108 05:53:27
Re: GramSchmidt matrix factorization in C++Hi; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #6 20130110 03:39:54
Re: GramSchmidt matrix factorization in C++Hi; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. 