Hello everybody, Mi name is Salomon and I'm a fortran user(This sounds like AA meeting). I'm new to the list and to fortran. So far I've been able to construct some programs with succes. However, rigth now I'm facing a problem that simply goes far beyond my undestanding. The problem I'm having is the following I have a program that has to multiply matrices, one of the matrices is symmetric and has the form S = BT.C.B*detj + S this matrix is in a do loop so it won't be symmetric until the end of the cycle. BT is the transpose of B and C is a 4*4 matrix. I've been playing with the coeffients of C, they are of the order of 1e10. When I use order of magnitude less than 1e9 the program works just fine, I get my symmetric matrix, but with values of 1e10 my result (S) is no longer symmetric. I tested my code in Matlab and works perfect, it doesnt matter the order of the coefficents of C. I declared C as REAL B(4,8) REAl S(8,8) REAL C(4,4) REAL C11,C12,C13,C33,C44 I already tried REAL(4) and REAL(8) and nothing happens. I use the gfortran compiler in linux. Is there anything I'm missing?? Thanks for your help ___________________________________________________________ Do You Yahoo!? La mejor conexión a Internet y <b >2GB</b> extra a tu correo por $100 al mes. http://net.yahoo.com.mx
