squenshl Messages 468 Reaction score 4 Thread starter Aug 14, 2009 #1 How do I reduce P = A(ATA)-1AT to P = BBT whenever the column vectors of A form an orthonormal set.
Peeter Messages 303 Reaction score 3 Aug 14, 2009 #2 If the columns are an orthonormal set, then A^T A == I (where I has rank of the number of columns). The proof is mainly writing out that product in block form.
If the columns are an orthonormal set, then A^T A == I (where I has rank of the number of columns). The proof is mainly writing out that product in block form.