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Solve Nonlinear System of Equations

  1. Dec 27, 2011 #1
    Hi, I have a set of vectors that I would like to solve for in a nonlinear system of equations.

    I have tried to use scipy.fsolve to solve the system, but without success. I believe the problem is that scipy expects the same number of inputs as outputs. I have a 12x1 input vector, but I can only generate 9 independent equations.

    I would appreciate any help with this, for example how I could over-constrain the problem, or am I missing something?

    The vectors {C,R1,R2,R3} are all (3x1). There are also a set of (3x1) vectors {S1,S2,S3} that are known.

    The equations are as follows:

    CTR1=S1 (1)

    CTR2=S2 (2)

    CTR3=S3 (3)

    and finally

    [R1 R2 R3]T[R1 R2 R3]=I

    which can be reduced to

    R1TR1=R2TR2=R3TR3=1 (4,5,6)

    R1TR2=R2TR3=R3TR1=0 (7,8,9)

    R2TR1=R3TR2=R1TR3=0 Would give me 12 equations, but they are exactly the same as Equations 7,8,9.

    So I dont know how to proceed. I would appreciate if anybody could point me in a direction, or to a matlab/scipy routine.
  2. jcsd
  3. Dec 27, 2011 #2
    I think I have it, I cannot solve the system without an additional set of constraints.
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