least square

[CYMTR]

         I ran the following standard example taken from IMSL(and also
            checked with Matlab ) for least square solution of Ax = b,
            where 

octave:4> A = [1,5,15,5;1, 4,17,4 ;1,7,14,7;1,3,18,3;1,1,15,1;\
              1,8,11,8;1,3,9,3;1,4,10,0]
A =

   1   5  15   5
   1   4  17   4
   1   7  14   7
   1   3  18   3
   1   1  15   1
   1   8  11   8
   1   3   9   3
   1   4  10   0

octave:5> b = [30;31;35;29;18;35;20;22]
b =

  30
  31
  35
  29
  18
  35
  20
  22

 octave:6> x = A\b
x =

  1.48165
  2.59948
  1.01204
  0.22104

The actual LEAST SQUARE solution for the overdetermines system 
 ( which is ,as I assume, not same as the minimum norm soln for 
  singular matrices ) is:

          X = .636, 2.845, 1.058, 000.
 with residuals  r = -.733, .996, -365, 783, -1.353, -.036, 1.306, -.597

 Does octave support a linear least square solving code or am I doing 
  something wrong? ( Mr. David Doolin suggested that I resubmit this ).

                                Thanking you,

                                sincerely,

                                A. K. Mitra, address@hidden
 



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