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DitzaN
Posts:
26
Registered:
6/2/09


qr decomposition
Posted:
Feb 8, 2011 7:05 AM


Hi,
I was using matlab 7.4(R2007a) Now I am using matlab7.11 (R2007b) I compared the results of qr function the input was 0.002567107834001 0.000011594153560 0.001071830879080 0.000348397823395 0.002671433293894 0.000451336098179 0.000000757384596 0.000000006341647 0.000000956196323 I didn't got the same answer in the two version the difference between the version is Q1Q
ans =
0 0.2690 0.0000 0 1.9818 0.0000 0 0.0001 0.0000
R1R
ans =
0 0 0 0 0.0053 0.0012 0 0 0
if I dividing them I got Q1./Q
ans =
1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000
R1./R
ans =
1.0000 1.0000 1.0000 NaN 1.0000 1.0000 NaN NaN 1.0000
why is this differences? Is this decomposition is not unique? Is there is way to get from 7.11 the same results as 7.4?
Thanks, Ditza



