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<DIV>Hi,</DIV>
<DIV>I am trying to write a program in python that solves a system of nonlinear equations using newton's method. I don't know what I am doing wrong. Please help</DIV>
<DIV> </DIV>
<DIV>from scipy import*</DIV>
<DIV> </DIV>
<DIV>x = array([0.0,0.0,0.0])<BR>n=len(x)<BR>tol= 0.00001<BR>N=30</DIV>
<DIV> </DIV>
<DIV>k=1<BR>while k <= N:<BR> def f(x):<BR> f= zeros((len(x)),float)<BR> f[0][k]= x[0][k]**2 + x[1][k]-37<BR> f[1][k]=x[0][k]- x[1][k]**2- 5<BR> f[2][k]= x[0][k] + x[1][k]+ x[2][k]- 3<BR> return f[k]<BR> def J(x):<BR> J= zeros((n,n),float)<BR> for i in range(n):<BR> ei=zeros(n,float)<BR> ei[i]=1.0<BR> J[:i]=(f(x[k]+tol*ei)-f(x[k]))/tol<BR> return J</DIV>
<DIV> </DIV>
<DIV> y[k] = -(J.I)*f[k]<BR> x[k+1]=x[k]+y[k]</DIV>
<DIV> </DIV>
<DIV>if sqrt(dot(f0,f0)/len(x)) < tol: print x<BR>else:<BR> k=k+1</DIV>
<DIV> </DIV>
<DIV>print 'Too many iterations'<BR></DIV></BODY><font face="Verdana,Arial,Helvetica,Trebuchet MS" size="1">
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