with text_io; use text_io;
with Standard_Natural_Vectors;
with Standard_Complex_Matrices; use Standard_Complex_Matrices;
with Standard_Complex_VecMats; use Standard_Complex_VecMats;
with Pieri_Root_Counts; use Pieri_Root_Counts;
package Pieri_Deformations is
-- DESCRIPTION :
-- Deformations that start at pairs of leaves satisfying Pieri's conditions.
procedure Deform_Pair
( file : in file_type; pnd : in Paired_Nodes; id : in natural;
f1,f2 : in Standard_Complex_Matrices.Matrix;
l1,l2 : in VecMat; ln : in Matrix; report,outlog : in boolean;
sol : in out Matrix );
-- DESCRIPTION :
-- Does one step in the Pieri deformation at the current pair and
-- moves down to the node below in the chains until the solution sol
-- meets all planes in l1,l2 and ln nontrivially.
-- ON ENTRY :
-- file for writing intermediate results;
-- pnd pair of nodes in a chain that starts at a pair of leaves
-- for which Pieri's condition is satisfied;
-- id identity number of the pair in the list of paired nodes;
-- f1 random upper triangular matrix with 1's on its anti-diagonal;
-- f2 random lower triangular matrix with 1's on its diagonal;
-- l1 first sequence of input planes;
-- l2 second sequence of input planes;
-- ln last input plane;
-- report indicates whether intermediate output during path tracking;
-- sol solution at the pair of nodes above the current pair.
-- ON ENTRY :
-- sol updated solution plane.
procedure Deform_Pairs
( file : in file_type; n,d : in natural;
lp : in List_of_Paired_Nodes; l1,l2 : in VecMat;
ln : in Matrix; report,outlog : in boolean; sols : out VecMat );
-- DESCRIPTION :
-- Performs the deformation of pairs for every pair in the list.
-- ON ENTRY :
-- file to write intermediate results;
-- n dimension of the space the planes all live in;
-- d dimension of the output planes;
-- lp list of paired nodes, satisfying Pieri's condition;
-- l1 first sequence of input planes,
-- l1(0) is spanned by first standard basis vectors;
-- l2 second sequence of input planes,
-- l2(0) is spanned by last standard basis vectors;
-- ln last input plane;
-- report indicates whether intermediate output during path tracking;
-- outlog if switched on, writes moving cycles and polynomial systems.
-- ON RETURN :
-- sols sequence of solution planes.
end Pieri_Deformations;