SP::Sp2TableVar
--
variable set for the SP package
SP::Sp2TableVar(expr)
expr | - | any expression |
The SP::Sp2TableVar
function returns a table whose entries describe the
set of all Schubert polynomials and variables that appear in a given
expression expr
.
The indices of the table are taken into the global variable SP::SPBases
.
For all bases of type _index
(SP::SPBasesIndexed
), the entry
consists of the set of all permutations that index the corresponding Schubert
polynomials in expr
.
For all bases of type DOM_IDENT
(SP::SPBasesString
), the entry
consists of the set of all integers that index the corresponding variable in
expr
.
An entry equal to an empty set means that the element does not appear in
expr
.
One can add a second argument to select some elements among those in
SP::SPBases
.
If the second argument is a set of names, then the restriction to this set of
indices of the table is returned.
In case the second argument is a single name, then the corresponding entry in
the table is returned instead of the table.
>> muEC::SP::Sp2TableVar(x1^3*x4*y4 + q*y6*X[4,1,3,2]*X[2,3,1]);
table( Pe = {}, YY = {}, Y = {}, XX = {}, X = {[2, 3, 1], [4, 1, 3, 2]}, y = {4, 6}, x = {1, 4} )
>> muEC::SP::Sp2TableVar(x1^3*x4*y4 + q*y6*X[4,1,3,2]*X[2,3,1], {X, x});
table( X = {[2, 3, 1], [4, 1, 3, 2]}, x = {1, 4} )
>> muEC::SP::Sp2TableVar(x1^3*x4*y4 + q*y6*X[4,1,3,2]*X[2,3,1], y);
{4, 6}
MuPAD Combinat, an open source algebraic combinatorics package