Re: [ublas] Solving linear equations in a loop (Optimization issues)

From: Nico Galoppo (nico_at_[hidden])
Date: 2007-03-03 09:58:04

Hi Sourabh,

I believe Gunther is trying to say that using unit_lower_tag() makes the 
following call solve the system (I+A)Y=B

solve(A, B, unit_lower_tag());

So, for your case, if you fill A with -lembda, you will effectively solve 
(I-lembda)Y=B

minuslembda = -lembda;
for (;;)
   solve(minuslembda, omega, unit_lower_tag());

It will be equivalent to the statement you gave below.

--nico

Sourabh wrote:
> Do you mean that I fill lembda with negative values and use this 
> statement:
> 
> solve (lembda, omega, unit_lower_tag ()) ?
> 
> will it solve the equation treating lemda as (I+lembda)
> Will it be equivalent to the following statement ?
> 
> lembda = I - lembda
> solve (lembda, omega, lower_tag ())
> 
> 

-- 
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