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## Re: Matrix Power (was Re: Matrix quotent)

 From: flatmax Subject: Re: Matrix Power (was Re: Matrix quotent) Date: Thu, 19 Oct 2000 14:14:40 +1100 (EST)

```I have found the function 'elem_xpow (const Matrix& a, const Matrix& b)'
and have altered it based on the assumption that the results are never
complex .... it was from the file 'src/xpow.cc'
It looks like so :
// -*- 4 -*-
Matrix
elem_xpow (const Matrix& a, const Matrix& b)
{

int nr = a.rows ();
int nc = a.cols ();

int b_nr = b.rows ();
int b_nc = b.cols ();

if (nr != b_nr || nc != b_nc)
{
gripe_nonconformant ("operator .^", nr, nc, b_nr, b_nc);
//return octave_value ();
}
Matrix result (nr, nc);

for (int j = 0; j < nc; j++)
for (int i = 0; i < nr; i++)
result (i, j) = pow (a (i, j), b (i, j));

return result;
}

Matt

On Thu, 19 Oct 2000, flatmax wrote:

> Ooops, I realise I actually want to find the power of one matrix raised to
> the other .... for example :
>    int r=64, p=3;
>    RowVector onesP(p+1,1);
>    ColumnVector onesR(r,1);
>    ColumnVector spanR(r);
>    RowVector spanP(p+1);
>
> In octave pseudo code I would like to find the following :
>       b=(spanR * onesP).^(onesR * spanP);
> Any ideas ?
> thanks
> Matt
>
>
>
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