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Problem with qrfac and Qrsolv(for least square) [message #57051]

Fri, 30 November 2007 14:53

coold
Messages: 8
Registered: December 2004

Junior Member

I was trying to solve a constrained least square problem with qrfac
and qrsolv but it stops at

idiag = lindgen(minmn)
r(idiag, idiag) = rdiag
I am wondering if I am making any mistake as I really would like to
use the QRdecomp routine.
************************************************
IDL>.run leastsq_decomp
IDL>leastsq_qrdecomp
pro leastsq_qrdecomp
;solve the equation A## X = B, in the least squares sense, where:
;A=[3,4] B=[4,1] ;;SIZE OF MATRICES

A = [[1,2,2],$
[4,5,6],$
[7,8,9],$
[1,1,1]]
print, A
B = [[1],[3],[5],[1]]
print, B

qrfac, a, r, ipvt, /PIVOT
x = qrsolv(a, r, b, PIVOTS=ipvt)
print, x
end

Thanks.

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Problem with qrfac and Qrsolv(for least square)

By: coold on Fri, 30 November 2007 14:53

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