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

**From:** Karl Meerbergen (*Karl.Meerbergen_at_[hidden]*)

**Date:** 2006-01-18 07:57:27

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Can we conclude that

1) 'Nested' collections are supported in containers and views (matrix

row, column, etc) only, but not in computational algorithms?

2) Those who want to use vector<vector<T>> etc in computations have to

implement their own.

3) GLAS should be relatively easy to extend, i.e. it should be possible

to write

glas::norm_1(v), where norm_1 is dispatched to a user defined function.

Karl

Wolfgang Bangerth wrote:

>>How should trans(v)*w be interpreted?

>>* result is a vector<double> which is the sum: sum_i v[i]*w[i] ?

>>* result is a vector<double> with element i being: trans(v)*w[i] ?

>>

>>

>

>I don't think there is a universal interpretation of what that expression

>should mean, so simply don't implement it. If someone wants to attach a

>particular meaning to it, they can always overload operators in their

>application programs.

>

>W.

>

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> www: http://www.math.tamu.edu/~bangerth/

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