wiki:PolynomialExpansion

Version 24 (modified by sili, 10 years ago) ( diff )

--

A = {{a0, a1}, {a1, a2}}, b = {b0, b1}

Step 1: r = b - Ax

r[0] = b0

r[1] = b1

Step 2: alpha = (r[i]*r[i]) / (p[i]*A[i][j]*p[j])

p[i]*(A[i][j]*p[j]) = a0*b02 + 2*a1*b0*b1 + a2*b12

alpha = (b02+b12) / ((b12)*a2+2*(b1*b0*a1)+(b02)*a0)

Step 3: r[i] = r - alpha * A[i][j] * p[j]

r[0] = (-b1*(-a1*b02 + a0*b0*b1 - a2*b0*b1 + a1*b12)) / (a0*b02 + 2*a1*b0*b1 + a2*b12)

r[1] = (b0*(-a1*b02 + a0*b0*b1 - a2*b0*b1 + a1*b12)) / (a0*b02 + 2*a1*b0*b1 + a2*b12)

Step 4: x[i] = x + alpha*p[i]

x[0] = (b0*(b02 + b12)) / (a0*b02 + 2*a1*b0*b1 + a2*b12)

x[1] = (b1*(b02 + b12)) / (a0*b02 + 2*a1*b0*b1 + a2*b12)

Step 5: beta = rsnew / rsold = (rk[i]*rk[i]) / (r[i]*r[i])

rsnew = ((b02 + b12)*(-a1*b02 + a0*b0*b1 - a2*b0*b1 + a1*b12)2) / (a0*b02 + 2*a1*b0*b1 + a2*b12)2

beta = (a1*b02 - a0*b0*b1 + a2*b0*b1 - a1*b12)2 / (a0*b02 + 2*a1*b0*b1 + a2*b12)2

Step 6: p[i] = rk[i] +beta * p

p[0] = (-1)*((a1*b0 + a2*b1)*(b02 + b12)*(-a1*b02 + a0*b0*b1 - a2*b0*b1 + a1*b12)) / (a0*b02 + 2*a1*b0*b1 + a2*b12)2

p[1] = ((a0*b0 + a1*b1)*(b02 + b12)*(-a1*b02 + a0*b0*b1 - a2*b0*b1 + a1*b12)) / (a0*b02 + 2*a1*b0*b1 + a2*b12)2

Step 7: alpha = (r[i]*r[i]) / (p[i]*A[i][j]*p[j])

p[i]*(A[i][j]*p[j]) = ((-a12 + a0*a2)*(b02 + b12)2*(-a1*b02 + a0*b0*b1 - a2*b0*b1 + a1*b12)2) / (a0*b02 + 2*a1*b0*b1 + a2*b12)3

alpha = (a0*b02 + 2*a1*b0*b1 + a2*b12) / ((-a12 + a0*a2) (b02 + b12))

Step 8: r[i] = r - alpha * A[i][j] * p[j]

r[0] = 0

r[1] = 0

Step 9: x[i] = x + alpha*p[i]

x[0] = (a2*b0 - a1*b1) / (a0*a2 - a12)

x[1] = (-a1*b0 + a0*b1) / (a0*a2 - a12)

assertion:

bncg[0] = A[0][0]*X[0] + A[0][1]*X[1] = a0*(a2*b0 - a1*b1) / (a0*a2 - a12) + a1*(-a1*b0 + a0*b1) / (a0*a2 - a12) = b0*(a0*a2-a12) / (a0*a2-a12) = b0

bncg[1] = A[1][0]*X[0] + A[1][1]*X[1] = a1*(a2*b0 - a1*b1) / (a0*a2 - a12) + a2*(-a1*b0 + a0*b1) / (a0*a2 - a12) = b1*(a0*a2-a12) / (a0*a2-a12) = b1

b[0] = b0

b[1] = b1

END

Attachments (4)

Download all attachments as: .zip

Note: See TracWiki for help on using the wiki.