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From: Hayati Ayguen (Ayguen_at_[hidden])
Date: 20010715 10:52:16
hello,
being new to mtl2.1.219, i have following questions:
1
is it possible to let mtl calculate the (in)homogene solution space of a
matrix A having rank(A) < min(A.nrows(),A.ncols()) with A.nrows() !=
A.ncols() ?
2
A being an incidence matrix describing a graph:
{ 1 , if i == start_node( edge(j) )
a(i,j) = { +1 , if i == end_node( edge(j) )
{ 0 , else
would it be possible to use a sparse matrix containing no double but
integer elements for the problem above?
example for a simple small graph:
=================================
N1 b N2 c N3
+++
  
a g d
  
+++
N6 f N5 e N4
A(6,7) * x(1,7) = b(1,6)
specially b = transposed( 0, 0, 0, 0, 0, 0 ).
so solving A * x = 0 with following A
[ 1 1 0 0 0 0 0  0 ]
[ 0 1 1 0 0 0 1  0 ]
A = [ 0 0 1 1 0 0 0  0 ]
[ 0 0 0 1 1 0 0  0 ]
[ 0 0 0 0 1 1 1  0 ]
[ 1 0 0 0 0 1 0  0 ]
should led to the solution space
[ 0 ] [ 1 0 ]
[ 0 ] [ 1 0 ]
[ 0 ] [ 1 1 ] [ alpha1 ]
X = x0 + X1 = [ 0 ] + [ 1 1 ] * [ alpha2 ]
[ 0 ] [ 1 1 ]
[ 0 ] [ 1 0 ]
[ 0 ] [ 0 1 ]
for any transposed(alpha1, alpha2)
thanks in advance
Hayati Ayguen
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