Computing the pseudo inverse of a matrix in R -

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i trying compute pseudo inverse of matrix, call m, might following way:

m=matrix(c(-1,-1,1,0,0,1),nrow=2,ncol=3)

what need left inverse of matrix, such that:

m_inv_l m=i

using mass package, able find right inverse:

m_inv_r=ginv(m)

where m m_inv_r=i.

is there way compute left inverse instead of right inverse? haven't been able find answer on forum.

thanks

i don't think possible in general - you're trying solve 9 linear equations 6 values. specifically, @ top row of inverse:

-1* minv[1,1] + -1*minv[1,2] = 1                     [1]  1* minv[1,1] +  0*minv[1,2] = 0 => minv[1,1]=0      [2]  0* minv[1,1] +  1*minv[1,2] = 0 => minv[1,2]=0      [3]

it should clear substituting [2] , [3] [1] produces contradiction.


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