Problem using Solve

*To*: mathgroup at smc.vnet.net*Subject*: [mg89728] Problem using Solve*From*: "Dario Caldara" <dario.caldara at gmail.com>*Date*: Thu, 19 Jun 2008 05:42:39 -0400 (EDT)

Dear Sirs, I am new to Mathematica. I am trying to solve a linear system of equations (28 equations/unknowns). The coefficients of this system of equations are function of a set of parameters (deep parameters of my model). I need to solve this system of equations for different values of the deep parameters. To solve the system I use the following command: solution = Solve[Thread[test4[[cho2]] == 0]]; I can solve the system of equations for some values of the parameters. But in most cases I get the following warning message: RowReduce::luc: "Result for RowReduce of badly conditioned matrix \ {{0.0920865234989278,0.*10^-16,0,0,0,0,0,0,0,0,<<19>>},<<9>>,<<18>>} \ may contain significant numerical errors" I do not know how to interpret and make good use of the information contained in this message. To what extend can I trust the output of Mathematica? Is there anything I can do to fix this problem? The parameter values I use are in a range for which - according to theory - a solution to the system exists. I apologize if my question is trivial or if I was not clear enough. I am ready to provide any further explanation Kind Regards Dario