From 22f06a7779d89461a090bf42ba2ff26e5fc4fca1 Mon Sep 17 00:00:00 2001 From: Michael Abed Date: Sun, 1 Apr 2012 15:09:30 -0400 Subject: computeA --- computeA.m | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) create mode 100755 computeA.m diff --git a/computeA.m b/computeA.m new file mode 100755 index 0000000..aa1ca08 --- /dev/null +++ b/computeA.m @@ -0,0 +1,32 @@ +function [ A ] = computeA( C, X, Y, Sx, Sy ) +% computes the A matrix for solving a truss + + [j, m] = size(C); + A = zeros(2*j, m+3); + for row = 1:j + for col = 1:m + if C(row,col) + p = findother(C(:,col), row); + p1 = [X(row), Y(row)]; + p2 = [X(p), Y(p)]; + d = distance(p1, p2); + A(row,col) = (X(p) - X(row))/d; + A(row+j,col) = (Y(p) - Y(row))/d; + end + end + end + A(m+1:m+3,1:j)=Sx; + A(m+1:m+3,j+1:2*j)=Sy; +end + +function [ p ] = findother(col, row) + for i = 1:size(col) + if col(i) ~= row && col(i) + p = i; + end + end +end + +function [ d ] = distance( p1, p2 ) + d = sqrt((p1(1)-p2(1))^2 + (p1(2)-p2(2))^2); +end \ No newline at end of file -- cgit v1.2.3