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Re: I have 51 linear equations, consisting of 51 unknowns. How to solve it in Matlab by using matrix?
Posted:
May 28, 2013 10:45 AM


"J K" <chemical2romance90@yahoo.com> wrote in message news:knvthf$87h$1@newscl01ah.mathworks.com... >> What do you mean by "separate the equations"? > > Let say I have 3 equations with 3 unknowns. > 1x1 + 2x2 + 3x3 = 100 > 4x1+ 5x2 + 6x3 = 200 > 7x1 + 8x2 + 9x3 = 300 > > Normally in Matlab, you will do this command in order to solve x1,x2,x3 > > p=[1 2 3; 4 5 7; 7 8 9]' > q=[100 200 300]' > x=inv(p)*q > > But let's say I don't want to use the method/way that I write. What other > options that I have in order to solve for the 51 unknowns?
If you want to leave the equations in the equation form (the first section above) instead of converting them into the matrixbased form (the second section above), you could do this using SOLVE from Symbolic Math Toolbox. If that's not an option then you MUST convert them from the equation form to the matrix form to solve them, and as Matt J said you should use the backslash operator NOT the INV function to solve the system.
 Steve Lord slord@mathworks.com To contact Technical Support use the Contact Us link on http://www.mathworks.com



