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Pseudo inverse: small deviations, large error
Posted:
Jan 12, 2013 11:33 PM


Hi,
Can someone plain why I get such huge errors with only slight deviations?
>> Hf Hf =
1.0e+003 *
1.6443 1.6516 1.6583 4.8373 4.8349 4.8334 4.6385 4.6418 4.6445 9.6014 9.6084 9.6154
>> [yl1 , yl3 , yl1  yl3 ] ans =
1.0e+006 *
0.2966 0.2972 0.0006 0.8705 0.8703 0.0002 0.8352 0.8355 0.0003 1.7288 1.7295 0.0006
This is the correct result:
>> Hf \ yl1 ans =
100.0000 75.0000 5.0000
And now:
>> Hf \ yl3 ans =
56.0412 72.5578 51.4007
... unuseable results. I have much redundancy available, I can make the rows of "Hf" very large but still get bad results.
Thanks, Peter



