## Glas :## Re: [glas] norms and inner products for vectors of matrices |

**From:** Neal Becker (*ndbecker2_at_[hidden]*)

**Date:** 2006-01-09 06:55:15

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On Sunday 08 January 2006 12:40 pm, Wolfgang Bangerth wrote:

> > Talking about vectors of matrices, we need to define algorithms for

> > those: let v be a vector of matrices, so v[i] is a matrix,

> >

> > Then norm_1 could be:

> > sum_i norm_1( v[i] )

> >

> > Norm_inf:

> > max_i norm_inf(v[i])

> >

> > and similarly for other norm functions.

> >

> > For the inner product, trans(v)*w is then

> > sum_i trans(v[i]) * w[i]

> >

> > Is this ok?

>

> Certainly, at least for the norm. For the inner product, should it be

> trans(v[i]) * w[i]

> or

> v[i] * w[i]

> I guess the former makes sense if one thinks of vectors that have a block

> structure (in your diction, each block would be a n times 1 matrix).

>

I think you want v[i] * conj (w[i]).

**Next message:**Karl Meerbergen: "Re: [glas] norms and inner products for vectors of matrices"**Previous message:**Wolfgang Bangerth: "Re: [glas] norms and inner products for vectors of matrices"**In reply to:**Wolfgang Bangerth: "Re: [glas] norms and inner products for vectors of matrices"**Next in thread:**Karl Meerbergen: "Re: [glas] norms and inner products for vectors of matrices"**Reply:**Karl Meerbergen: "Re: [glas] norms and inner products for vectors of matrices"**Reply:**Andrew Lumsdaine: "Re: [glas] norms and inner products for vectors of matrices"