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OrderVariables -- Option to set the order of indexed variables

Description

This option can be used to specify the order of the indexed variables of the polynomial ring containing the ideals, when calling lexIdeal or stronglyStableIdeals giving as input only the number of variables of the polynomial ring. If OrderVariables is set to Up then x_i < x_j iff i < j, otherwise if OrderVariables is set to Down then x_i < x_j iff i > j.

The default is Down.

i1 : lexIdeal(3, 3, OrderVariables=>Down)

                 3
o1 = ideal (x , x )
             0   1

o1 : Ideal of QQ[x ..x ]
                  0   2
i2 : stronglyStableIdeals(3, 3, OrderVariables=>Up)

                  3           2         2
o2 = {ideal (x , x ), ideal (x , x x , x )}
              2   1           1   2 1   2

o2 : List

Functions with optional argument named OrderVariables:

For the programmer

The object OrderVariables is a symbol.